diff --git a/examples/capture_shapes.rs b/examples/capture_shapes.rs
new file mode 100644
index 0000000..91e0617
--- /dev/null
+++ b/examples/capture_shapes.rs
@@ -0,0 +1,167 @@
+//! Records the *shape* of real Invoice Ninja responses as test fixtures.
+//!
+//! Mock servers written from the upstream source have been wrong about the
+//! real thing before (system-log timestamps, `/subscriptions/steps`), so the
+//! offline suite benefits from fixtures that came from a real server. This
+//! writes them without writing any data: every string becomes `""`, every
+//! number `0`, every bool `false`, and an array keeps only its first element.
+//! What survives is the key names and the JSON types, which is what decoding
+//! depends on. `tests/real_shapes.rs` refuses to pass if a fixture holds
+//! anything else.
+//!
+//! GET requests only, so it is safe against any instance, but it still reads
+//! real records in memory. Review the diff before committing.
+//!
+//! ```sh
+//! IN_BASE_URL=http://localhost:8080/api/v1 IN_API_TOKEN=... \
+//!     cargo run --example capture_shapes
+//! ```
+//!
+//! A resource with no rows on the instance writes nothing and is reported as
+//! skipped, since an empty list says nothing about a row's shape. Populate a
+//! disposable instance and re-run to capture more.
+
+use std::fs;
+use std::path::Path;
+
+use serde_json::{json, Value};
+
+/// Resources captured as a one-row list. The name doubles as the fixture
+/// filename.
+const LISTS: &[&str] = &[
+    "activities",
+    "bank_integrations",
+    "bank_transaction_rules",
+    "bank_transactions",
+    "client_gateway_tokens",
+    "clients",
+    "companies",
+    "company_gateways",
+    "credits",
+    "designs",
+    "documents",
+    "expense_categories",
+    "expenses",
+    "group_settings",
+    "invoices",
+    "locations",
+    "payment_terms",
+    "payments",
+    "products",
+    "projects",
+    "purchase_orders",
+    "quotes",
+    "recurring_expenses",
+    "recurring_invoices",
+    "recurring_quotes",
+    "subscriptions",
+    "system_logs",
+    "tags",
+    "task_schedulers",
+    "task_statuses",
+    "tasks",
+    "tax_rates",
+    "tokens",
+    "users",
+    "vendors",
+    "webhooks",
+];
+
+/// Endpoints with no `data` envelope, captured whole.
+const BARE: &[(&str, &str)] = &[
+    ("statics", "statics"),
+    ("health_check", "health_check"),
+    ("subscription_steps", "subscriptions/steps"),
+    ("activity_feed", "activities?rows=1&reactv2=1"),
+];
+
+/// Replaces every value with a placeholder of the same JSON type.
+fn shape(value: &Value) -> Value {
+    match value {
+        Value::Null => Value::Null,
+        Value::Bool(_) => json!(false),
+        Value::Number(n) if n.is_f64() => json!(0.0),
+        Value::Number(_) => json!(0),
+        Value::String(_) => json!(""),
+        // Only the first element: a list's rows share a shape, and keeping
+        // all of them would just be size.
+        Value::Array(items) => Value::Array(items.first().map(shape).into_iter().collect()),
+        Value::Object(map) => {
+            Value::Object(map.iter().map(|(k, v)| (k.clone(), shape(v))).collect())
+        }
+    }
+}
+
+#[tokio::main]
+async fn main() {
+    let base = std::env::var("IN_BASE_URL").expect("set IN_BASE_URL");
+    let token = std::env::var("IN_API_TOKEN").expect("set IN_API_TOKEN");
+    let base = base.trim_end_matches('/');
+    let out = Path::new("tests/fixtures");
+    fs::create_dir_all(out).expect("create tests/fixtures");
+
+    let http = reqwest::Client::new();
+    let get = |path: String| {
+        let http = http.clone();
+        let token = token.clone();
+        let url = format!("{base}/{path}");
+        async move {
+            let response = http
+                .get(url)
+                .header("X-Api-Token", token)
+                .header("Accept", "application/json")
+                .header("X-Requested-With", "XMLHttpRequest")
+                .send()
+                .await
+                .map_err(|e| e.to_string())?;
+            let status = response.status();
+            let body = response.text().await.map_err(|e| e.to_string())?;
+            if !status.is_success() {
+                return Err(format!("HTTP {status}"));
+            }
+            serde_json::from_str::<Value>(&body).map_err(|e| e.to_string())
+        }
+    };
+
+    for name in LISTS {
+        // Deleted and archived rows included: on a disposable instance they
+        // are often all there is.
+        // `system_logs` answers the status filter with a 500, so fall back to
+        // the plain list when the filtered one fails.
+        let filtered = format!("{name}?per_page=1&status=active,archived,deleted");
+        let result = match get(filtered).await {
+            Ok(body) => Ok(body),
+            Err(_) => get(format!("{name}?per_page=1")).await,
+        };
+        match result {
+            Ok(body) => match body
+                .get("data")
+                .and_then(Value::as_array)
+                .and_then(|d| d.first())
+            {
+                Some(row) => {
+                    write(out, name, &json!({ "data": [shape(row)] }));
+                    println!("  captured  {name}");
+                }
+                None => println!("  skipped   {name}: no rows on this instance"),
+            },
+            Err(e) => println!("  FAILED    {name}: {e}"),
+        }
+    }
+
+    for (name, path) in BARE {
+        match get((*path).to_string()).await {
+            Ok(body) => {
+                write(out, name, &shape(&body));
+                println!("  captured  {name}");
+            }
+            Err(e) => println!("  FAILED    {name}: {e}"),
+        }
+    }
+}
+
+fn write(dir: &Path, name: &str, value: &Value) {
+    let mut text = serde_json::to_string_pretty(value).expect("serialise fixture");
+    text.push('\n');
+    fs::write(dir.join(format!("{name}.json")), text).expect("write fixture");
+}
diff --git a/examples/seed_sample_data.rs b/examples/seed_sample_data.rs
new file mode 100644
index 0000000..e2dc698
--- /dev/null
+++ b/examples/seed_sample_data.rs
@@ -0,0 +1,232 @@
+//! Fills a **disposable** Invoice Ninja instance with one record of each
+//! common kind, so `capture_shapes` has real rows to take shapes from.
+//!
+//! ```sh
+//! IN_SMOKE_WRITE_HOST=localhost IN_BASE_URL=http://localhost:8080/api/v1 \
+//!     IN_API_TOKEN=... cargo run --example seed_sample_data
+//! ```
+//!
+//! **Never run this against production.** It creates records, advances
+//! number sequences, and may fire webhooks. It uses the smoke test's guard:
+//! `IN_SMOKE_WRITE_HOST` must equal the host in `IN_BASE_URL`. Nothing is
+//! deleted afterwards; the instance is meant to be thrown away.
+//!
+//! Each step is independent: one that fails (a validation rule this script
+//! did not anticipate) is reported and the rest carry on, with anything that
+//! needed it skipped.
+
+use std::future::Future;
+use std::process::ExitCode;
+
+use invoiceninjars::{Error, InvoiceNinjaClient};
+use serde::de::DeserializeOwned;
+use serde_json::{json, Value};
+
+fn model<T: DeserializeOwned>(value: Value) -> T {
+    serde_json::from_value(value).expect("seed body matches the model")
+}
+
+fn describe(error: &Error) -> String {
+    match error {
+        Error::Api { errors, .. } if !errors.is_empty() => format!("{error} {errors:?}"),
+        _ => error.to_string(),
+    }
+}
+
+/// Runs one creation, reporting the outcome and returning the new id.
+async fn step<T>(name: &str, call: impl Future<Output = invoiceninjars::Result<T>>) -> Option<T> {
+    match call.await {
+        Ok(created) => {
+            println!("  created  {name}");
+            Some(created)
+        }
+        Err(e) => {
+            println!("  FAILED   {name}: {}", describe(&e));
+            None
+        }
+    }
+}
+
+#[tokio::main]
+async fn main() -> ExitCode {
+    let base_url = std::env::var("IN_BASE_URL").expect("set IN_BASE_URL");
+    let token = std::env::var("IN_API_TOKEN").expect("set IN_API_TOKEN");
+    let host = reqwest::Url::parse(&base_url)
+        .ok()
+        .and_then(|u| u.host_str().map(str::to_string))
+        .unwrap_or_default();
+    if std::env::var("IN_SMOKE_WRITE_HOST").as_deref() != Ok(host.as_str()) {
+        eprintln!("refusing to write: set IN_SMOKE_WRITE_HOST={host} to confirm this instance is disposable");
+        return ExitCode::FAILURE;
+    }
+    let c = InvoiceNinjaClient::new(&base_url, token).expect("client");
+    println!("seeding {host}");
+
+    let line =
+        json!([{ "product_key": "seed-product", "quantity": 1, "cost": 10.0, "notes": "seed" }]);
+
+    let client_id = step(
+        "client",
+        c.create_client(&model(json!({
+            "name": "seed-client",
+            "contacts": [{ "first_name": "Seed", "last_name": "Contact", "email": "seed@example.com" }],
+        }))),
+    )
+    .await
+    .and_then(|x| x.id);
+    let vendor_id = step(
+        "vendor",
+        c.create_vendor(&model(json!({ "name": "seed-vendor" }))),
+    )
+    .await
+    .and_then(|x| x.id);
+
+    step(
+        "product",
+        c.create_product(&model(
+            json!({ "product_key": "seed-product", "price": 10.0 }),
+        )),
+    )
+    .await;
+    step(
+        "tax_rate",
+        c.create_tax_rate(&model(json!({ "name": "seed-tax", "rate": 5.0 }))),
+    )
+    .await;
+    step(
+        "payment_term",
+        c.create_payment_term(&model(json!({ "name": "seed-term", "num_days": 15 }))),
+    )
+    .await;
+    step(
+        "expense_category",
+        c.create_expense_category(&model(json!({ "name": "seed-category" }))),
+    )
+    .await;
+    step(
+        "tag",
+        c.create_tag(&model(
+            json!({ "name": "seed-tag", "entity_type": "client" }),
+        )),
+    )
+    .await;
+    step(
+        "group_setting",
+        c.create_group_setting(&model(json!({ "name": "seed-group" }))),
+    )
+    .await;
+    step(
+        "webhook",
+        c.create_webhook(&model(
+            json!({ "event_id": "1", "target_url": "https://example.com/seed-hook" }),
+        )),
+    )
+    .await;
+    step(
+        "expense",
+        c.create_expense(&model(
+            json!({ "amount": 5.0, "public_notes": "seed", "vendor_id": vendor_id }),
+        )),
+    )
+    .await;
+    step(
+        "recurring_expense",
+        c.create_recurring_expense(&model(
+            json!({ "amount": 5.0, "frequency_id": 5, "vendor_id": vendor_id }),
+        )),
+    )
+    .await;
+
+    if let Some(vendor_id) = &vendor_id {
+        step(
+            "purchase_order",
+            c.create_purchase_order(&model(
+                json!({ "vendor_id": vendor_id, "line_items": line }),
+            )),
+        )
+        .await;
+    }
+
+    let Some(client_id) = client_id else {
+        println!("no client, so the client-dependent records are skipped");
+        return ExitCode::FAILURE;
+    };
+
+    step(
+        "location",
+        c.create_location(&model(
+            json!({ "name": "seed-location", "client_id": client_id, "address1": "1 Seed St" }),
+        )),
+    )
+    .await;
+    step(
+        "project",
+        c.create_project(&model(
+            json!({ "name": "seed-project", "client_id": client_id }),
+        )),
+    )
+    .await;
+    step(
+        "task",
+        c.create_task(&model(
+            json!({ "description": "seed task", "client_id": client_id }),
+        )),
+    )
+    .await;
+    step(
+        "quote",
+        c.create_quote(&model(
+            json!({ "client_id": client_id, "line_items": line }),
+        )),
+    )
+    .await;
+    step(
+        "credit",
+        c.create_credit(&model(
+            json!({ "client_id": client_id, "line_items": line }),
+        )),
+    )
+    .await;
+    step(
+        "recurring_invoice",
+        c.create_recurring_invoice(&model(
+            json!({ "client_id": client_id, "frequency_id": 5, "line_items": line }),
+        )),
+    )
+    .await;
+    // Expected to 500 on 5.13.50: the `recurring_quotes` table has no
+    // `design_id` column, so the server's own insert fails. Not an SDK bug.
+    step(
+        "recurring_quote",
+        c.create_recurring_quote(&model(
+            json!({ "client_id": client_id, "frequency_id": 5, "line_items": line }),
+        )),
+    )
+    .await;
+
+    let invoice = step(
+        "invoice",
+        c.create_invoice(&model(
+            json!({ "client_id": client_id, "line_items": line }),
+        )),
+    )
+    .await;
+    if let Some(id) = invoice.and_then(|i| i.id) {
+        // A payment can only be applied to an invoice that has been sent.
+        if step("invoice mark_sent", c.mark_invoice_sent(&id))
+            .await
+            .is_some()
+        {
+            step(
+                "payment",
+                c.create_payment(&model(json!({
+                    "client_id": client_id,
+                    "amount": 5.0,
+                    "invoices": [{ "invoice_id": id, "amount": 5.0 }],
+                }))),
+            )
+            .await;
+        }
+    }
+    ExitCode::SUCCESS
+}
diff --git a/tests/fixtures/activities.json b/tests/fixtures/activities.json
new file mode 100644
index 0000000..6f0c4d3
--- /dev/null
+++ b/tests/fixtures/activities.json
@@ -0,0 +1,29 @@
+{
+  "data": [
+    {
+      "activity_type_id": "",
+      "client_id": "",
+      "company_id": "",
+      "contact_id": "",
+      "created_at": 0,
+      "credit_id": "",
+      "expense_id": "",
+      "id": "",
+      "invoice_id": "",
+      "ip": "",
+      "is_system": false,
+      "notes": "",
+      "payment_id": "",
+      "purchase_order_id": "",
+      "quote_id": "",
+      "recurring_expense_id": "",
+      "recurring_invoice_id": "",
+      "task_id": "",
+      "token_id": "",
+      "updated_at": 0,
+      "user_id": "",
+      "vendor_contact_id": "",
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/activity_feed.json b/tests/fixtures/activity_feed.json
new file mode 100644
index 0000000..2e343e6
--- /dev/null
+++ b/tests/fixtures/activity_feed.json
@@ -0,0 +1,24 @@
+{
+  "data": [
+    {
+      "activity_type_id": 0,
+      "created_at": 0,
+      "hashed_id": "",
+      "id": "",
+      "ip": "",
+      "notes": "",
+      "purchase_order": {
+        "hashed_id": "",
+        "label": ""
+      },
+      "user": {
+        "hashed_id": "",
+        "label": ""
+      },
+      "vendor": {
+        "hashed_id": "",
+        "label": ""
+      }
+    }
+  ]
+}
diff --git a/tests/fixtures/clients.json b/tests/fixtures/clients.json
new file mode 100644
index 0000000..741dd0c
--- /dev/null
+++ b/tests/fixtures/clients.json
@@ -0,0 +1,114 @@
+{
+  "data": [
+    {
+      "address1": "",
+      "address2": "",
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "balance": 0,
+      "city": "",
+      "classification": "",
+      "client_hash": "",
+      "contacts": [
+        {
+          "archived_at": 0,
+          "can_sign": false,
+          "cc_only": false,
+          "contact_key": "",
+          "created_at": 0,
+          "custom_value1": "",
+          "custom_value2": "",
+          "custom_value3": "",
+          "custom_value4": "",
+          "email": "",
+          "first_name": "",
+          "id": "",
+          "is_locked": false,
+          "is_primary": false,
+          "last_login": 0,
+          "last_name": "",
+          "link": "",
+          "password": "",
+          "phone": "",
+          "send_email": false,
+          "updated_at": 0
+        }
+      ],
+      "country_id": "",
+      "created_at": 0,
+      "credit_balance": 0,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "display_name": "",
+      "documents": [
+        {
+          "archived_at": 0,
+          "assigned_user_id": "",
+          "created_at": 0,
+          "disk": "",
+          "documentable_id": "",
+          "documentable_type": "",
+          "hash": "",
+          "height": 0,
+          "id": "",
+          "is_default": false,
+          "is_deleted": false,
+          "is_public": false,
+          "link": "",
+          "name": "",
+          "preview": "",
+          "project_id": "",
+          "size": 0,
+          "type": "",
+          "updated_at": 0,
+          "url": "",
+          "user_id": "",
+          "vendor_id": "",
+          "width": 0
+        }
+      ],
+      "e_invoice": {},
+      "gateway_tokens": [],
+      "group_settings_id": "",
+      "has_valid_vat_number": false,
+      "id": "",
+      "id_number": "",
+      "industry_id": "",
+      "is_deleted": false,
+      "is_tax_exempt": false,
+      "last_login": 0,
+      "locations": [],
+      "name": "",
+      "number": "",
+      "paid_to_date": 0,
+      "payment_balance": 0,
+      "phone": "",
+      "postal_code": "",
+      "private_notes": "",
+      "public_notes": "",
+      "routing_id": "",
+      "settings": {
+        "currency_id": "",
+        "entity": "",
+        "industry_id": null,
+        "size_id": null
+      },
+      "shipping_address1": "",
+      "shipping_address2": "",
+      "shipping_city": "",
+      "shipping_country_id": "",
+      "shipping_postal_code": "",
+      "shipping_state": "",
+      "size_id": "",
+      "state": "",
+      "tags": [],
+      "tax_info": {},
+      "updated_at": 0,
+      "user_id": "",
+      "vat_number": "",
+      "website": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/companies.json b/tests/fixtures/companies.json
new file mode 100644
index 0000000..de12598
--- /dev/null
+++ b/tests/fixtures/companies.json
@@ -0,0 +1,1059 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "auto_start_tasks": false,
+      "calculate_expense_tax_by_amount": false,
+      "calculate_taxes": false,
+      "client_can_register": false,
+      "client_registration_fields": [
+        {
+          "key": "",
+          "required": false,
+          "visible": false
+        }
+      ],
+      "company_key": "",
+      "convert_expense_currency": false,
+      "convert_payment_currency": false,
+      "convert_products": false,
+      "convert_rate_to_client": false,
+      "created_at": 0,
+      "custom_fields": {},
+      "custom_surcharge_taxes1": false,
+      "custom_surcharge_taxes2": false,
+      "custom_surcharge_taxes3": false,
+      "custom_surcharge_taxes4": false,
+      "default_password_timeout": 0,
+      "default_quantity": false,
+      "default_task_is_date_based": false,
+      "documents": [],
+      "e_invoice": {},
+      "enable_applying_payments": false,
+      "enable_modules": false,
+      "enable_product_cost": false,
+      "enable_product_discount": false,
+      "enable_product_quantity": false,
+      "enable_shop_api": false,
+      "enabled_expense_tax_rates": 0,
+      "enabled_item_tax_rates": 0,
+      "enabled_modules": 0,
+      "enabled_tax_rates": 0,
+      "expense_amount_is_pretax": false,
+      "expense_inclusive_taxes": false,
+      "expense_mailbox": "",
+      "expense_mailbox_active": false,
+      "fill_products": false,
+      "first_day_of_week": "",
+      "first_month_of_year": "",
+      "google_analytics_key": "",
+      "google_analytics_url": "",
+      "has_e_invoice_certificate": false,
+      "has_e_invoice_certificate_passphrase": false,
+      "hide_empty_columns_on_pdf": false,
+      "id": "",
+      "inbound_mailbox_allow_clients": false,
+      "inbound_mailbox_allow_company_users": false,
+      "inbound_mailbox_allow_unknown": false,
+      "inbound_mailbox_allow_vendors": false,
+      "inbound_mailbox_blacklist": "",
+      "inbound_mailbox_whitelist": "",
+      "industry_id": "",
+      "inventory_notification_threshold": 0,
+      "invoice_expense_documents": false,
+      "invoice_task_datelog": false,
+      "invoice_task_documents": false,
+      "invoice_task_hours": false,
+      "invoice_task_item_description": false,
+      "invoice_task_lock": false,
+      "invoice_task_project": false,
+      "invoice_task_project_header": false,
+      "invoice_task_timelog": false,
+      "is_disabled": false,
+      "is_large": false,
+      "legal_entity_id": null,
+      "mark_expenses_invoiceable": false,
+      "mark_expenses_paid": false,
+      "markdown_email_enabled": false,
+      "markdown_enabled": false,
+      "matomo_id": "",
+      "matomo_url": "",
+      "notify_vendor_when_paid": false,
+      "oauth_password_required": false,
+      "origin_tax_data": {},
+      "portal_domain": "",
+      "portal_mode": "",
+      "quickbooks": null,
+      "report_include_deleted": false,
+      "report_include_drafts": false,
+      "session_timeout": 0,
+      "settings": {
+        "accept_client_input_quote_approval": false,
+        "address1": "",
+        "address2": "",
+        "all_pages_footer": false,
+        "all_pages_header": false,
+        "allow_billable_task_items": false,
+        "auto_archive_invoice": false,
+        "auto_archive_invoice_cancelled": false,
+        "auto_archive_quote": false,
+        "auto_bill": "",
+        "auto_bill_date": "",
+        "auto_bill_standard_invoices": false,
+        "auto_convert_quote": false,
+        "auto_email_invoice": false,
+        "bcc_email": "",
+        "besr_id": "",
+        "brevo_secret": "",
+        "city": "",
+        "classification": "",
+        "client_can_register": false,
+        "client_initiated_payments": false,
+        "client_initiated_payments_minimum": 0,
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+        "client_number_counter": 0,
+        "client_number_pattern": "",
+        "client_online_payment_notification": false,
+        "client_portal_allow_over_payment": false,
+        "client_portal_allow_under_payment": false,
+        "client_portal_enable_uploads": false,
+        "client_portal_privacy_policy": "",
+        "client_portal_terms": "",
+        "client_portal_under_payment_minimum": 0,
+        "company_gateway_ids": "",
+        "company_logo": "",
+        "company_logo_size": "",
+        "counter_number_applied": "",
+        "counter_padding": 0,
+        "country_id": "",
+        "credit_design_id": "",
+        "credit_footer": "",
+        "credit_number_counter": 0,
+        "credit_number_pattern": "",
+        "credit_terms": "",
+        "currency_id": "",
+        "custom_message_dashboard": "",
+        "custom_message_paid_invoice": "",
+        "custom_message_unapproved_quote": "",
+        "custom_message_unpaid_invoice": "",
+        "custom_sending_email": "",
+        "custom_value1": "",
+        "custom_value2": "",
+        "custom_value3": "",
+        "custom_value4": "",
+        "date_format_id": "",
+        "default_expense_payment_type_id": "",
+        "default_task_rate": 0,
+        "delivery_note_design_id": "",
+        "document_email_attachment": false,
+        "documents_public_by_default": false,
+        "e_expense_forward_email": "",
+        "e_invoice_forward_email": "",
+        "e_invoice_type": "",
+        "e_quote_type": "",
+        "email": "",
+        "email_alignment": "",
+        "email_from_name": "",
+        "email_quote_subject_reminder1": "",
+        "email_quote_template_reminder1": "",
+        "email_sending_method": "",
+        "email_signature": "",
+        "email_style": "",
+        "email_style_custom": "",
+        "email_subject_credit": "",
+        "email_subject_custom1": "",
+        "email_subject_custom2": "",
+        "email_subject_custom3": "",
+        "email_subject_invoice": "",
+        "email_subject_payment": "",
+        "email_subject_payment_failed": "",
+        "email_subject_payment_partial": "",
+        "email_subject_purchase_order": "",
+        "email_subject_quote": "",
+        "email_subject_reminder1": "",
+        "email_subject_reminder2": "",
+        "email_subject_reminder3": "",
+        "email_subject_reminder_endless": "",
+        "email_subject_statement": "",
+        "email_template_credit": "",
+        "email_template_custom1": "",
+        "email_template_custom2": "",
+        "email_template_custom3": "",
+        "email_template_invoice": "",
+        "email_template_payment": "",
+        "email_template_payment_failed": "",
+        "email_template_payment_partial": "",
+        "email_template_purchase_order": "",
+        "email_template_quote": "",
+        "email_template_reminder1": "",
+        "email_template_reminder2": "",
+        "email_template_reminder3": "",
+        "email_template_reminder_endless": "",
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+        "embed_documents": false,
+        "enable_client_portal": false,
+        "enable_client_portal_dashboard": false,
+        "enable_client_portal_password": false,
+        "enable_client_portal_tasks": false,
+        "enable_client_profile_update": false,
+        "enable_e_invoice": false,
+        "enable_email_markup": false,
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+        "expense_number_counter": 0,
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+        "france_reporting_enabled": false,
+        "france_reporting_schedule": "",
+        "global_tag_inheritance": false,
+        "gmail_sending_user_id": "",
+        "hide_empty_columns_on_pdf": false,
+        "hide_paid_to_date": false,
+        "id_number": "",
+        "inclusive_taxes": false,
+        "invoice_design_id": "",
+        "invoice_footer": "",
+        "invoice_labels": "",
+        "invoice_number_counter": 0,
+        "invoice_number_pattern": "",
+        "invoice_taxes": 0,
+        "invoice_terms": "",
+        "language_id": "",
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+        "late_fee_percent3": 0,
+        "lock_invoices": "",
+        "mailgun_domain": "",
+        "mailgun_endpoint": "",
+        "mailgun_secret": "",
+        "merge_e_invoice_to_pdf": false,
+        "military_time": false,
+        "name": "",
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+        "page_size": "",
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+        "payment_flow": "",
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+        "payment_number_pattern": "",
+        "payment_receipt_design_id": "",
+        "payment_refund_design_id": "",
+        "payment_terms": "",
+        "payment_type_id": "",
+        "pdf_email_attachment": false,
+        "pdf_variables": {
+          "client_details": [
+            ""
+          ],
+          "company_address": [
+            ""
+          ],
+          "company_details": [
+            ""
+          ],
+          "credit_details": [
+            ""
+          ],
+          "delivery_note_columns": [
+            ""
+          ],
+          "invoice_details": [
+            ""
+          ],
+          "product_columns": [
+            ""
+          ],
+          "product_quote_columns": [
+            ""
+          ],
+          "purchase_order_details": [
+            ""
+          ],
+          "quote_details": [
+            ""
+          ],
+          "statement_credit_columns": [
+            ""
+          ],
+          "statement_details": [
+            ""
+          ],
+          "statement_invoice_columns": [
+            ""
+          ],
+          "statement_payment_columns": [
+            ""
+          ],
+          "statement_unapplied_columns": [
+            ""
+          ],
+          "task_columns": [
+            ""
+          ],
+          "total_columns": [
+            ""
+          ],
+          "vendor_details": [
+            ""
+          ]
+        },
+        "phone": "",
+        "portal_custom_css": "",
+        "portal_custom_footer": "",
+        "portal_custom_head": "",
+        "portal_custom_js": "",
+        "portal_design_id": "",
+        "postal_code": "",
+        "postmark_secret": "",
+        "preference_product_notes_for_html_view": false,
+        "primary_color": "",
+        "primary_font": "",
+        "project_number_counter": 0,
+        "project_number_pattern": "",
+        "purchase_order_design_id": "",
+        "purchase_order_footer": "",
+        "purchase_order_number_counter": 0,
+        "purchase_order_number_pattern": "",
+        "purchase_order_public_notes": "",
+        "purchase_order_terms": "",
+        "qr_iban": "",
+        "quote_design_id": "",
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+        "quote_number_pattern": "",
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+        "recurring_expense_number_pattern": "",
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+        "recurring_invoice_number_pattern": "",
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+        "recurring_quote_number_counter": 0,
+        "recurring_quote_number_pattern": "",
+        "reminder_send_time": 0,
+        "reply_to_email": "",
+        "reply_to_name": "",
+        "require_invoice_signature": false,
+        "require_purchase_order_signature": false,
+        "require_quote_signature": false,
+        "reset_counter_date": "",
+        "reset_counter_frequency_id": "",
+        "schedule_reminder1": "",
+        "schedule_reminder2": "",
+        "schedule_reminder3": "",
+        "secondary_color": "",
+        "secondary_font": "",
+        "send_email_on_mark_paid": false,
+        "send_reminders": false,
+        "ses_access_key": "",
+        "ses_from_address": "",
+        "ses_region": "",
+        "ses_secret_key": "",
+        "ses_topic_arn": "",
+        "shared_invoice_credit_counter": false,
+        "shared_invoice_quote_counter": false,
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+        "show_accept_quote_terms": false,
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+        "show_pdfhtml_on_mobile": false,
+        "show_shipping_address": false,
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+        "signature_on_pdf": false,
+        "skip_automatic_email_with_peppol": false,
+        "state": "",
+        "statement_design_id": "",
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+        "task_number_counter": 0,
+        "task_number_pattern": "",
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+        "tax_name1": "",
+        "tax_name2": "",
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+        "tax_rate2": 0,
+        "tax_rate3": 0,
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+        "ticket_number_pattern": "",
+        "timezone_id": "",
+        "translations": {},
+        "ubl_email_attachment": false,
+        "unlock_invoice_documents_after_payment": false,
+        "use_credits_payment": "",
+        "use_unapplied_payment": "",
+        "valid_until": "",
+        "vat_number": "",
+        "vendor_number_counter": 0,
+        "vendor_number_pattern": "",
+        "vendor_portal_enable_uploads": false,
+        "website": ""
+      },
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+      "show_product_details": false,
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+      "show_tasks_table": false,
+      "size_id": "",
+      "slack_webhook_url": "",
+      "smtp_encryption": "",
+      "smtp_host": "",
+      "smtp_local_domain": "",
+      "smtp_password": "",
+      "smtp_port": 0,
+      "smtp_username": "",
+      "smtp_verify_peer": false,
+      "stock_notification": false,
+      "stop_on_unpaid_recurring": false,
+      "subdomain": "",
+      "tax_data": {
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+        "acts_as_sender": false,
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+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "MI": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "MN": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "MO": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "MS": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "MT": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "NC": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "ND": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "NE": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "NH": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "NJ": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "NM": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "NV": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "NY": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "OH": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "OK": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "OR": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "PA": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "RI": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "SC": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "SD": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "TN": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "TX": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "UT": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "VA": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "VT": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "WA": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0.0,
+                "vat_number": ""
+              },
+              "WI": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "WV": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              },
+              "WY": {
+                "apply_tax": false,
+                "tax_name": "",
+                "tax_rate": 0,
+                "vat_number": ""
+              }
+            },
+            "tax_all_subregions": false
+          }
+        },
+        "seller_subregion": "",
+        "version": ""
+      },
+      "track_inventory": false,
+      "update_products": false,
+      "updated_at": 0,
+      "use_comma_as_decimal_place": false,
+      "use_credits_payment": "",
+      "use_quote_terms_on_conversion": false
+    }
+  ]
+}
diff --git a/tests/fixtures/credits.json b/tests/fixtures/credits.json
new file mode 100644
index 0000000..d59a819
--- /dev/null
+++ b/tests/fixtures/credits.json
@@ -0,0 +1,139 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "backup": {
+        "adjustable_amount": 0,
+        "cancellation": {
+          "adjustment": 0,
+          "status_id": 0
+        },
+        "child_invoice_ids": [],
+        "document_type": null,
+        "e_invoice_cleared_at": null,
+        "e_invoice_status": null,
+        "guid": "",
+        "notes": null,
+        "parent_invoice_id": null,
+        "parent_invoice_number": null,
+        "redirect": null
+      },
+      "balance": 0,
+      "client_id": "",
+      "created_at": 0,
+      "custom_surcharge1": 0,
+      "custom_surcharge2": 0,
+      "custom_surcharge3": 0,
+      "custom_surcharge4": 0,
+      "custom_surcharge_tax1": false,
+      "custom_surcharge_tax2": false,
+      "custom_surcharge_tax3": false,
+      "custom_surcharge_tax4": false,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "design_id": "",
+      "discount": 0,
+      "documents": [],
+      "due_date": "",
+      "e_invoice": {},
+      "entity_type": "",
+      "exchange_rate": 0,
+      "footer": "",
+      "has_expenses": false,
+      "has_tasks": false,
+      "id": "",
+      "invitations": [
+        {
+          "archived_at": 0,
+          "can_sign": false,
+          "client_contact_id": "",
+          "created_at": 0,
+          "email_error": "",
+          "email_status": "",
+          "id": "",
+          "key": "",
+          "link": "",
+          "message_id": "",
+          "opened_date": "",
+          "sent_date": "",
+          "updated_at": 0,
+          "viewed_date": ""
+        }
+      ],
+      "invoice_id": "",
+      "is_amount_discount": false,
+      "is_deleted": false,
+      "last_sent_date": "",
+      "line_items": [
+        {
+          "cost": 0,
+          "custom_value1": "",
+          "custom_value2": "",
+          "custom_value3": "",
+          "custom_value4": "",
+          "date": "",
+          "discount": 0,
+          "expense_id": "",
+          "gross_line_total": 0,
+          "income_account_id": "",
+          "is_amount_discount": false,
+          "line_total": 0,
+          "net_cost": 0,
+          "notes": "",
+          "product_cost": 0,
+          "product_key": "",
+          "quantity": 0,
+          "sort_id": "",
+          "tags": "",
+          "task_id": "",
+          "tax_amount": 0,
+          "tax_id": "",
+          "tax_name1": "",
+          "tax_name2": "",
+          "tax_name3": "",
+          "tax_rate1": 0,
+          "tax_rate2": 0,
+          "tax_rate3": 0,
+          "type_id": "",
+          "unit_code": ""
+        }
+      ],
+      "location_id": "",
+      "next_send_date": "",
+      "number": "",
+      "paid_to_date": 0,
+      "partial": 0,
+      "partial_due_date": "",
+      "po_number": "",
+      "private_notes": "",
+      "project_id": "",
+      "public_notes": "",
+      "reminder1_sent": "",
+      "reminder2_sent": "",
+      "reminder3_sent": "",
+      "reminder_last_sent": "",
+      "status_id": "",
+      "subscription_id": "",
+      "sync": null,
+      "tags": [],
+      "tax_info": {},
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "terms": "",
+      "total_taxes": 0,
+      "updated_at": 0,
+      "user_id": "",
+      "uses_inclusive_taxes": false,
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/designs.json b/tests/fixtures/designs.json
new file mode 100644
index 0000000..2a94a48
--- /dev/null
+++ b/tests/fixtures/designs.json
@@ -0,0 +1,25 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "created_at": 0,
+      "design": {
+        "body": "",
+        "footer": "",
+        "header": "",
+        "includes": "",
+        "product": "",
+        "task": ""
+      },
+      "entities": "",
+      "id": "",
+      "is_active": false,
+      "is_custom": false,
+      "is_deleted": false,
+      "is_free": false,
+      "is_template": false,
+      "name": "",
+      "updated_at": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/documents.json b/tests/fixtures/documents.json
new file mode 100644
index 0000000..acfe02b
--- /dev/null
+++ b/tests/fixtures/documents.json
@@ -0,0 +1,29 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "created_at": 0,
+      "disk": "",
+      "documentable_id": "",
+      "documentable_type": "",
+      "hash": "",
+      "height": 0,
+      "id": "",
+      "is_default": false,
+      "is_deleted": false,
+      "is_public": false,
+      "link": "",
+      "name": "",
+      "preview": "",
+      "project_id": "",
+      "size": 0,
+      "type": "",
+      "updated_at": 0,
+      "url": "",
+      "user_id": "",
+      "vendor_id": "",
+      "width": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/expense_categories.json b/tests/fixtures/expense_categories.json
new file mode 100644
index 0000000..ad7048c
--- /dev/null
+++ b/tests/fixtures/expense_categories.json
@@ -0,0 +1,14 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "color": "",
+      "created_at": 0,
+      "id": "",
+      "is_deleted": false,
+      "name": "",
+      "updated_at": 0,
+      "user_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/expenses.json b/tests/fixtures/expenses.json
new file mode 100644
index 0000000..7c70083
--- /dev/null
+++ b/tests/fixtures/expenses.json
@@ -0,0 +1,55 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "bank_id": "",
+      "calculate_tax_by_amount": false,
+      "category_id": "",
+      "client_id": "",
+      "created_at": 0,
+      "currency_id": "",
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "documents": [],
+      "e_invoice": {},
+      "entity_type": "",
+      "exchange_rate": 0,
+      "expense_currency_id": "",
+      "foreign_amount": 0,
+      "id": "",
+      "invoice_currency_id": "",
+      "invoice_documents": false,
+      "invoice_id": "",
+      "is_deleted": false,
+      "number": "",
+      "payment_date": "",
+      "payment_type_id": "",
+      "private_notes": "",
+      "project_id": "",
+      "public_notes": "",
+      "recurring_expense_id": "",
+      "should_be_invoiced": false,
+      "tags": [],
+      "tax_amount1": 0,
+      "tax_amount2": 0,
+      "tax_amount3": 0,
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "transaction_id": "",
+      "transaction_reference": "",
+      "updated_at": 0,
+      "user_id": "",
+      "uses_inclusive_taxes": false,
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/group_settings.json b/tests/fixtures/group_settings.json
new file mode 100644
index 0000000..6122763
--- /dev/null
+++ b/tests/fixtures/group_settings.json
@@ -0,0 +1,16 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "created_at": 0,
+      "documents": [],
+      "id": "",
+      "is_deleted": false,
+      "name": "",
+      "settings": {
+        "entity": ""
+      },
+      "updated_at": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/health_check.json b/tests/fixtures/health_check.json
new file mode 100644
index 0000000..f073e50
--- /dev/null
+++ b/tests/fixtures/health_check.json
@@ -0,0 +1,37 @@
+{
+  "api_version": "",
+  "cache_enabled": false,
+  "env_writable": false,
+  "exchange_rate_api_not_configured": false,
+  "exec": false,
+  "extensions": [
+    {
+      "gd": false
+    }
+  ],
+  "file_permissions": "",
+  "flutter_renderer": "",
+  "is_docker": false,
+  "jobs_pending": 0,
+  "mail_mailer": "",
+  "open_basedir": false,
+  "pdf_engine": "",
+  "pending_migrations": false,
+  "phantom_enabled": false,
+  "php_version": {
+    "current_php_cli_version": "",
+    "current_php_version": "",
+    "is_okay": false,
+    "memory_limit": "",
+    "minimum_php_version": ""
+  },
+  "queue": "",
+  "queue_data": {
+    "failed": 0,
+    "last_error": "",
+    "pending": 0
+  },
+  "simple_db_check": false,
+  "system_health": false,
+  "trailing_slash": false
+}
diff --git a/tests/fixtures/invoices.json b/tests/fixtures/invoices.json
new file mode 100644
index 0000000..de369dd
--- /dev/null
+++ b/tests/fixtures/invoices.json
@@ -0,0 +1,140 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "auto_bill_enabled": false,
+      "backup": {
+        "adjustable_amount": 0,
+        "cancellation": {
+          "adjustment": 0,
+          "status_id": 0
+        },
+        "child_invoice_ids": [],
+        "document_type": null,
+        "e_invoice_cleared_at": null,
+        "e_invoice_status": null,
+        "guid": "",
+        "notes": null,
+        "parent_invoice_id": null,
+        "parent_invoice_number": null,
+        "redirect": null
+      },
+      "balance": 0,
+      "client_id": "",
+      "created_at": 0,
+      "custom_surcharge1": 0,
+      "custom_surcharge2": 0,
+      "custom_surcharge3": 0,
+      "custom_surcharge4": 0,
+      "custom_surcharge_tax1": false,
+      "custom_surcharge_tax2": false,
+      "custom_surcharge_tax3": false,
+      "custom_surcharge_tax4": false,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "design_id": "",
+      "discount": 0,
+      "documents": [],
+      "due_date": "",
+      "e_invoice": {},
+      "entity_type": "",
+      "exchange_rate": 0,
+      "footer": "",
+      "has_expenses": false,
+      "has_tasks": false,
+      "id": "",
+      "invitations": [
+        {
+          "archived_at": 0,
+          "can_sign": false,
+          "client_contact_id": "",
+          "created_at": 0,
+          "email_error": "",
+          "email_status": "",
+          "id": "",
+          "key": "",
+          "link": "",
+          "message_id": "",
+          "opened_date": "",
+          "sent_date": "",
+          "updated_at": 0,
+          "viewed_date": ""
+        }
+      ],
+      "is_amount_discount": false,
+      "is_deleted": false,
+      "last_sent_date": "",
+      "line_items": [
+        {
+          "cost": 0,
+          "custom_value1": "",
+          "custom_value2": "",
+          "custom_value3": "",
+          "custom_value4": "",
+          "date": "",
+          "discount": 0,
+          "expense_id": "",
+          "gross_line_total": 0,
+          "income_account_id": "",
+          "is_amount_discount": false,
+          "line_total": 0,
+          "net_cost": 0,
+          "notes": "",
+          "product_cost": 0,
+          "product_key": "",
+          "quantity": 0,
+          "sort_id": "",
+          "tags": "",
+          "task_id": "",
+          "tax_amount": 0,
+          "tax_id": "",
+          "tax_name1": "",
+          "tax_name2": "",
+          "tax_name3": "",
+          "tax_rate1": 0,
+          "tax_rate2": 0,
+          "tax_rate3": 0,
+          "type_id": "",
+          "unit_code": ""
+        }
+      ],
+      "location_id": "",
+      "next_send_date": "",
+      "number": "",
+      "paid_to_date": 0,
+      "partial": 0,
+      "partial_due_date": "",
+      "po_number": "",
+      "private_notes": "",
+      "project_id": "",
+      "public_notes": "",
+      "recurring_id": "",
+      "reminder1_sent": "",
+      "reminder2_sent": "",
+      "reminder3_sent": "",
+      "reminder_last_sent": "",
+      "status_id": "",
+      "subscription_id": "",
+      "sync": null,
+      "tags": [],
+      "tax_info": {},
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "terms": "",
+      "total_taxes": 0,
+      "updated_at": 0,
+      "user_id": "",
+      "uses_inclusive_taxes": false,
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/locations.json b/tests/fixtures/locations.json
new file mode 100644
index 0000000..24a12e7
--- /dev/null
+++ b/tests/fixtures/locations.json
@@ -0,0 +1,27 @@
+{
+  "data": [
+    {
+      "address1": "",
+      "address2": "",
+      "archived_at": 0,
+      "city": "",
+      "client_id": "",
+      "country_id": "",
+      "created_at": 0,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "id": "",
+      "is_deleted": false,
+      "is_shipping_location": false,
+      "name": "",
+      "postal_code": "",
+      "state": "",
+      "tax_data": {},
+      "updated_at": 0,
+      "user_id": "",
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/payment_terms.json b/tests/fixtures/payment_terms.json
new file mode 100644
index 0000000..28f5300
--- /dev/null
+++ b/tests/fixtures/payment_terms.json
@@ -0,0 +1,13 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "created_at": 0,
+      "id": "",
+      "is_deleted": false,
+      "name": "",
+      "num_days": 0,
+      "updated_at": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/payments.json b/tests/fixtures/payments.json
new file mode 100644
index 0000000..ba60a00
--- /dev/null
+++ b/tests/fixtures/payments.json
@@ -0,0 +1,52 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "applied": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "client_contact_id": "",
+      "client_id": "",
+      "company_gateway_id": "",
+      "created_at": 0,
+      "currency_id": "",
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "documents": [],
+      "exchange_currency_id": "",
+      "exchange_rate": 0,
+      "gateway_type_id": "",
+      "id": "",
+      "invitation_id": "",
+      "is_deleted": false,
+      "is_manual": false,
+      "number": "",
+      "paymentables": [
+        {
+          "amount": 0,
+          "archived_at": 0,
+          "created_at": 0,
+          "id": "",
+          "invoice_id": "",
+          "payment_id": "",
+          "refunded": 0,
+          "updated_at": 0
+        }
+      ],
+      "private_notes": "",
+      "project_id": "",
+      "refunded": 0,
+      "status_id": "",
+      "tags": [],
+      "transaction_id": "",
+      "transaction_reference": "",
+      "type_id": "",
+      "updated_at": 0,
+      "user_id": "",
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/products.json b/tests/fixtures/products.json
new file mode 100644
index 0000000..22731f0
--- /dev/null
+++ b/tests/fixtures/products.json
@@ -0,0 +1,37 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "cost": 0,
+      "created_at": 0,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "documents": [],
+      "id": "",
+      "in_stock_quantity": 0,
+      "income_account_id": "",
+      "is_deleted": false,
+      "max_quantity": 0,
+      "notes": "",
+      "price": 0,
+      "product_image": "",
+      "product_key": "",
+      "quantity": 0,
+      "stock_notification": false,
+      "stock_notification_threshold": 0,
+      "tags": [],
+      "tax_id": "",
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "updated_at": 0,
+      "user_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/projects.json b/tests/fixtures/projects.json
new file mode 100644
index 0000000..62eec85
--- /dev/null
+++ b/tests/fixtures/projects.json
@@ -0,0 +1,30 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "budgeted_amount": 0,
+      "budgeted_hours": 0,
+      "client_id": "",
+      "color": "",
+      "created_at": 0,
+      "current_hours": 0,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "documents": [],
+      "due_date": "",
+      "id": "",
+      "is_deleted": false,
+      "name": "",
+      "number": "",
+      "private_notes": "",
+      "public_notes": "",
+      "tags": [],
+      "task_rate": 0,
+      "updated_at": 0,
+      "user_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/purchase_orders.json b/tests/fixtures/purchase_orders.json
new file mode 100644
index 0000000..0185bd3
--- /dev/null
+++ b/tests/fixtures/purchase_orders.json
@@ -0,0 +1,93 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "balance": 0,
+      "client_id": "",
+      "created_at": 0,
+      "currency_id": "",
+      "custom_surcharge1": 0,
+      "custom_surcharge2": 0,
+      "custom_surcharge3": 0,
+      "custom_surcharge4": 0,
+      "custom_surcharge_tax1": false,
+      "custom_surcharge_tax2": false,
+      "custom_surcharge_tax3": false,
+      "custom_surcharge_tax4": false,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "design_id": "",
+      "discount": 0,
+      "documents": [],
+      "due_date": "",
+      "e_invoice": {},
+      "entity_type": "",
+      "exchange_rate": 0,
+      "expense_id": "",
+      "footer": "",
+      "has_expenses": false,
+      "has_tasks": false,
+      "id": "",
+      "invitations": [
+        {
+          "archived_at": 0,
+          "can_sign": false,
+          "created_at": 0,
+          "email_error": "",
+          "email_status": "",
+          "id": "",
+          "key": "",
+          "link": "",
+          "message_id": "",
+          "opened_date": "",
+          "sent_date": "",
+          "updated_at": 0,
+          "vendor_contact_id": "",
+          "viewed_date": ""
+        }
+      ],
+      "invoice_id": "",
+      "is_amount_discount": false,
+      "is_deleted": false,
+      "last_sent_date": "",
+      "line_items": [],
+      "location_id": "",
+      "next_send_date": "",
+      "number": "",
+      "paid_to_date": 0,
+      "partial": 0,
+      "partial_due_date": "",
+      "po_number": "",
+      "private_notes": "",
+      "project_id": "",
+      "public_notes": "",
+      "quote_id": "",
+      "reminder1_sent": "",
+      "reminder2_sent": "",
+      "reminder3_sent": "",
+      "reminder_last_sent": "",
+      "status_id": "",
+      "subscription_id": "",
+      "sync": null,
+      "tags": [],
+      "tax_info": {},
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "terms": "",
+      "total_taxes": 0,
+      "updated_at": 0,
+      "user_id": "",
+      "uses_inclusive_taxes": false,
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/quotes.json b/tests/fixtures/quotes.json
new file mode 100644
index 0000000..c54b226
--- /dev/null
+++ b/tests/fixtures/quotes.json
@@ -0,0 +1,123 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "balance": 0,
+      "client_id": "",
+      "created_at": 0,
+      "custom_surcharge1": 0,
+      "custom_surcharge2": 0,
+      "custom_surcharge3": 0,
+      "custom_surcharge4": 0,
+      "custom_surcharge_tax1": false,
+      "custom_surcharge_tax2": false,
+      "custom_surcharge_tax3": false,
+      "custom_surcharge_tax4": false,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "design_id": "",
+      "discount": 0,
+      "documents": [],
+      "due_date": "",
+      "e_invoice": {},
+      "entity_type": "",
+      "exchange_rate": 0,
+      "footer": "",
+      "has_expenses": false,
+      "has_tasks": false,
+      "id": "",
+      "invitations": [
+        {
+          "archived_at": 0,
+          "can_sign": false,
+          "client_contact_id": "",
+          "created_at": 0,
+          "email_error": "",
+          "email_status": "",
+          "id": "",
+          "key": "",
+          "link": "",
+          "message_id": "",
+          "opened_date": "",
+          "sent_date": "",
+          "updated_at": 0,
+          "viewed_date": ""
+        }
+      ],
+      "invoice_id": "",
+      "is_amount_discount": false,
+      "is_deleted": false,
+      "last_sent_date": "",
+      "line_items": [
+        {
+          "cost": 0,
+          "custom_value1": "",
+          "custom_value2": "",
+          "custom_value3": "",
+          "custom_value4": "",
+          "date": "",
+          "discount": 0,
+          "expense_id": "",
+          "gross_line_total": 0,
+          "income_account_id": "",
+          "is_amount_discount": false,
+          "line_total": 0,
+          "net_cost": 0,
+          "notes": "",
+          "product_cost": 0,
+          "product_key": "",
+          "quantity": 0,
+          "sort_id": "",
+          "tags": "",
+          "task_id": "",
+          "tax_amount": 0,
+          "tax_id": "",
+          "tax_name1": "",
+          "tax_name2": "",
+          "tax_name3": "",
+          "tax_rate1": 0,
+          "tax_rate2": 0,
+          "tax_rate3": 0,
+          "type_id": "",
+          "unit_code": ""
+        }
+      ],
+      "location_id": "",
+      "next_send_date": "",
+      "number": "",
+      "paid_to_date": 0,
+      "partial": 0,
+      "partial_due_date": "",
+      "po_number": "",
+      "private_notes": "",
+      "project_id": "",
+      "public_notes": "",
+      "reminder1_sent": "",
+      "reminder2_sent": "",
+      "reminder3_sent": "",
+      "reminder_last_sent": "",
+      "status_id": "",
+      "subscription_id": "",
+      "sync": null,
+      "tags": [],
+      "tax_info": {},
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "terms": "",
+      "total_taxes": 0,
+      "updated_at": 0,
+      "user_id": "",
+      "uses_inclusive_taxes": false,
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/recurring_expenses.json b/tests/fixtures/recurring_expenses.json
new file mode 100644
index 0000000..83eb589
--- /dev/null
+++ b/tests/fixtures/recurring_expenses.json
@@ -0,0 +1,59 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "bank_id": "",
+      "calculate_tax_by_amount": false,
+      "category_id": "",
+      "client_id": "",
+      "created_at": 0,
+      "currency_id": "",
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "documents": [],
+      "entity_type": "",
+      "exchange_rate": 0,
+      "foreign_amount": 0,
+      "frequency_id": "",
+      "id": "",
+      "invoice_currency_id": "",
+      "invoice_documents": false,
+      "invoice_id": "",
+      "is_deleted": false,
+      "last_sent_date": "",
+      "next_send_date": "",
+      "number": "",
+      "payment_date": "",
+      "payment_type_id": "",
+      "private_notes": "",
+      "project_id": "",
+      "public_notes": "",
+      "recurring_dates": [],
+      "recurring_expense_currency_id": "",
+      "remaining_cycles": 0,
+      "should_be_invoiced": false,
+      "status_id": "",
+      "tags": [],
+      "tax_amount1": 0,
+      "tax_amount2": 0,
+      "tax_amount3": 0,
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "transaction_id": "",
+      "transaction_reference": "",
+      "updated_at": 0,
+      "user_id": "",
+      "uses_inclusive_taxes": false,
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/recurring_invoices.json b/tests/fixtures/recurring_invoices.json
new file mode 100644
index 0000000..1a9f6f2
--- /dev/null
+++ b/tests/fixtures/recurring_invoices.json
@@ -0,0 +1,90 @@
+{
+  "data": [
+    {
+      "amount": 0,
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "auto_bill": "",
+      "auto_bill_enabled": false,
+      "balance": 0,
+      "client_id": "",
+      "created_at": 0,
+      "custom_surcharge1": 0,
+      "custom_surcharge2": 0,
+      "custom_surcharge3": 0,
+      "custom_surcharge4": 0,
+      "custom_surcharge_tax1": false,
+      "custom_surcharge_tax2": false,
+      "custom_surcharge_tax3": false,
+      "custom_surcharge_tax4": false,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "design_id": "",
+      "discount": 0,
+      "documents": [],
+      "due_date": "",
+      "due_date_days": "",
+      "e_invoice": {},
+      "entity_type": "",
+      "exchange_rate": 0,
+      "footer": "",
+      "frequency_id": "",
+      "has_expenses": false,
+      "has_tasks": false,
+      "id": "",
+      "invitations": [
+        {
+          "archived_at": 0,
+          "can_sign": false,
+          "client_contact_id": "",
+          "created_at": 0,
+          "email_error": "",
+          "email_status": "",
+          "id": "",
+          "key": "",
+          "link": "",
+          "message_id": "",
+          "opened_date": "",
+          "sent_date": "",
+          "updated_at": 0,
+          "viewed_date": ""
+        }
+      ],
+      "is_amount_discount": false,
+      "is_deleted": false,
+      "last_sent_date": "",
+      "line_items": [],
+      "location_id": "",
+      "next_send_date": "",
+      "next_send_datetime": "",
+      "number": "",
+      "paid_to_date": 0,
+      "partial": 0,
+      "partial_due_date": "",
+      "po_number": "",
+      "private_notes": "",
+      "project_id": "",
+      "public_notes": "",
+      "recurring_dates": [],
+      "remaining_cycles": 0,
+      "status_id": "",
+      "subscription_id": "",
+      "tags": [],
+      "tax_name1": "",
+      "tax_name2": "",
+      "tax_name3": "",
+      "tax_rate1": 0,
+      "tax_rate2": 0,
+      "tax_rate3": 0,
+      "terms": "",
+      "total_taxes": 0,
+      "updated_at": 0,
+      "user_id": "",
+      "uses_inclusive_taxes": false,
+      "vendor_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/statics.json b/tests/fixtures/statics.json
new file mode 100644
index 0000000..99f791b
--- /dev/null
+++ b/tests/fixtures/statics.json
@@ -0,0 +1,185 @@
+{
+  "bulk_updates": {
+    "client": [
+      ""
+    ],
+    "expense": [
+      ""
+    ],
+    "recurring_invoice": [
+      ""
+    ],
+    "task": [
+      ""
+    ]
+  },
+  "countries": [
+    {
+      "capital": "",
+      "citizenship": "",
+      "country_code": "",
+      "currency": "",
+      "currency_code": "",
+      "currency_sub_unit": "",
+      "decimal_separator": "",
+      "eea": false,
+      "full_name": "",
+      "id": "",
+      "iso_3166_2": "",
+      "iso_3166_3": "",
+      "name": "",
+      "region_code": "",
+      "sub_region_code": "",
+      "swap_currency_symbol": false,
+      "swap_postal_code": false,
+      "thousand_separator": ""
+    }
+  ],
+  "currencies": [
+    {
+      "code": "",
+      "decimal_separator": "",
+      "exchange_rate": 0,
+      "id": "",
+      "name": "",
+      "precision": 0,
+      "swap_currency_symbol": false,
+      "symbol": "",
+      "thousand_separator": ""
+    }
+  ],
+  "date_formats": [
+    {
+      "format": "",
+      "format_dart": "",
+      "format_moment": "",
+      "id": ""
+    }
+  ],
+  "datetime_formats": [
+    {
+      "format": "",
+      "format_dart": "",
+      "format_moment": "",
+      "id": ""
+    }
+  ],
+  "gateways": [
+    {
+      "created_at": 0,
+      "default_gateway_type_id": "",
+      "fields": "",
+      "id": "",
+      "is_offsite": false,
+      "is_secure": false,
+      "key": "",
+      "name": "",
+      "options": {
+        "1": {
+          "refund": false,
+          "token_billing": false,
+          "webhooks": [
+            ""
+          ]
+        },
+        "2": {
+          "refund": false,
+          "token_billing": false,
+          "webhooks": [
+            ""
+          ]
+        }
+      },
+      "provider": "",
+      "site_url": "",
+      "sort_order": 0,
+      "updated_at": 0,
+      "visible": false
+    }
+  ],
+  "industries": [
+    {
+      "id": "",
+      "name": ""
+    }
+  ],
+  "languages": [
+    {
+      "id": "",
+      "locale": "",
+      "name": ""
+    }
+  ],
+  "license_key": false,
+  "payment_types": [
+    {
+      "gateway_type_id": 0,
+      "id": "",
+      "name": ""
+    }
+  ],
+  "sizes": [
+    {
+      "id": "",
+      "name": ""
+    }
+  ],
+  "templates": {
+    "invoice": {
+      "body": "",
+      "subject": ""
+    },
+    "partial_payment": {
+      "body": "",
+      "subject": ""
+    },
+    "payment": {
+      "body": "",
+      "subject": ""
+    },
+    "payment_failed": {
+      "body": "",
+      "subject": ""
+    },
+    "purchase_order": {
+      "body": "",
+      "subject": ""
+    },
+    "quote": {
+      "body": "",
+      "subject": ""
+    },
+    "quote_reminder1": {
+      "body": "",
+      "subject": ""
+    },
+    "reminder1": {
+      "body": "",
+      "subject": ""
+    },
+    "reminder2": {
+      "body": "",
+      "subject": ""
+    },
+    "reminder3": {
+      "body": "",
+      "subject": ""
+    },
+    "reminder_endless": {
+      "body": "",
+      "subject": ""
+    },
+    "statement": {
+      "body": "",
+      "subject": ""
+    }
+  },
+  "timezones": [
+    {
+      "id": "",
+      "location": "",
+      "name": "",
+      "utc_offset": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/subscription_steps.json b/tests/fixtures/subscription_steps.json
new file mode 100644
index 0000000..c3350ec
--- /dev/null
+++ b/tests/fixtures/subscription_steps.json
@@ -0,0 +1,18 @@
+{
+  "App\\Livewire\\BillingPortal\\Authentication\\Login": {
+    "dependencies": [],
+    "id": ""
+  },
+  "App\\Livewire\\BillingPortal\\Authentication\\Register": {
+    "dependencies": [],
+    "id": ""
+  },
+  "App\\Livewire\\BillingPortal\\Authentication\\RegisterOrLogin": {
+    "dependencies": [],
+    "id": ""
+  },
+  "App\\Livewire\\BillingPortal\\Cart\\Cart": {
+    "dependencies": [],
+    "id": ""
+  }
+}
diff --git a/tests/fixtures/system_logs.json b/tests/fixtures/system_logs.json
new file mode 100644
index 0000000..3593786
--- /dev/null
+++ b/tests/fixtures/system_logs.json
@@ -0,0 +1,16 @@
+{
+  "data": [
+    {
+      "category_id": 0,
+      "client_id": "",
+      "company_id": "",
+      "created_at": 0,
+      "event_id": 0,
+      "id": "",
+      "log": "",
+      "type_id": 0,
+      "updated_at": 0,
+      "user_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/tags.json b/tests/fixtures/tags.json
new file mode 100644
index 0000000..c7d2d38
--- /dev/null
+++ b/tests/fixtures/tags.json
@@ -0,0 +1,14 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "color": null,
+      "created_at": 0,
+      "entity_type": "",
+      "id": "",
+      "is_deleted": false,
+      "name": "",
+      "updated_at": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/task_statuses.json b/tests/fixtures/task_statuses.json
new file mode 100644
index 0000000..d6b0e91
--- /dev/null
+++ b/tests/fixtures/task_statuses.json
@@ -0,0 +1,14 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "color": "",
+      "created_at": 0,
+      "id": "",
+      "is_deleted": false,
+      "name": "",
+      "status_order": 0,
+      "updated_at": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/tasks.json b/tests/fixtures/tasks.json
new file mode 100644
index 0000000..90cda5a
--- /dev/null
+++ b/tests/fixtures/tasks.json
@@ -0,0 +1,36 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "client_id": "",
+      "created_at": 0,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "date": "",
+      "description": "",
+      "documents": [],
+      "due_date": "",
+      "duration": 0,
+      "estimated_duration": null,
+      "id": "",
+      "invoice_id": "",
+      "is_date_based": false,
+      "is_deleted": false,
+      "is_running": false,
+      "meta": {},
+      "number": "",
+      "project_id": "",
+      "rate": 0,
+      "status_id": "",
+      "status_order": null,
+      "status_sort_order": 0,
+      "tags": [],
+      "time_log": "",
+      "updated_at": 0,
+      "user_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/tax_rates.json b/tests/fixtures/tax_rates.json
new file mode 100644
index 0000000..29dd3c2
--- /dev/null
+++ b/tests/fixtures/tax_rates.json
@@ -0,0 +1,13 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "created_at": 0,
+      "id": "",
+      "is_deleted": false,
+      "name": "",
+      "rate": 0,
+      "updated_at": 0
+    }
+  ]
+}
diff --git a/tests/fixtures/tokens.json b/tests/fixtures/tokens.json
new file mode 100644
index 0000000..bd8fe44
--- /dev/null
+++ b/tests/fixtures/tokens.json
@@ -0,0 +1,15 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "created_at": 0,
+      "id": "",
+      "is_deleted": false,
+      "is_system": false,
+      "name": "",
+      "token": "",
+      "updated_at": 0,
+      "user_id": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/users.json b/tests/fixtures/users.json
new file mode 100644
index 0000000..f298049
--- /dev/null
+++ b/tests/fixtures/users.json
@@ -0,0 +1,44 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "created_at": 0,
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "email": "",
+      "email_verified_at": 0,
+      "first_name": "",
+      "google_2fa_secret": false,
+      "has_password": false,
+      "id": "",
+      "is_deleted": false,
+      "language_id": "",
+      "last_confirmed_email_address": "",
+      "last_login": 0,
+      "last_name": "",
+      "oauth_provider_id": "",
+      "oauth_user_token": "",
+      "passkey_count": 0,
+      "passkey_enabled": false,
+      "phone": "",
+      "referral_code": "",
+      "referral_meta": {
+        "enterprise": 0,
+        "free": 0,
+        "pro": 0
+      },
+      "settings": {
+        "calendar_connection": {
+          "email": "",
+          "status": ""
+        }
+      },
+      "signature": "",
+      "updated_at": 0,
+      "user_logged_in_notification": false,
+      "verified_phone_number": false
+    }
+  ]
+}
diff --git a/tests/fixtures/vendors.json b/tests/fixtures/vendors.json
new file mode 100644
index 0000000..5489379
--- /dev/null
+++ b/tests/fixtures/vendors.json
@@ -0,0 +1,63 @@
+{
+  "data": [
+    {
+      "address1": "",
+      "address2": "",
+      "archived_at": 0,
+      "assigned_user_id": "",
+      "city": "",
+      "classification": "",
+      "contacts": [
+        {
+          "archived_at": 0,
+          "can_sign": false,
+          "cc_only": false,
+          "created_at": 0,
+          "custom_value1": "",
+          "custom_value2": "",
+          "custom_value3": "",
+          "custom_value4": "",
+          "email": "",
+          "first_name": "",
+          "id": "",
+          "is_primary": false,
+          "last_login": 0,
+          "last_name": "",
+          "link": "",
+          "password": "",
+          "phone": "",
+          "send_email": false,
+          "updated_at": 0
+        }
+      ],
+      "country_id": "",
+      "created_at": 0,
+      "currency_id": "",
+      "custom_value1": "",
+      "custom_value2": "",
+      "custom_value3": "",
+      "custom_value4": "",
+      "display_name": "",
+      "documents": [],
+      "id": "",
+      "id_number": "",
+      "is_deleted": false,
+      "is_tax_exempt": false,
+      "language_id": "",
+      "last_login": 0,
+      "name": "",
+      "number": "",
+      "phone": "",
+      "postal_code": "",
+      "private_notes": "",
+      "public_notes": "",
+      "routing_id": "",
+      "state": "",
+      "tags": [],
+      "updated_at": 0,
+      "user_id": "",
+      "vat_number": "",
+      "website": ""
+    }
+  ]
+}
diff --git a/tests/fixtures/webhooks.json b/tests/fixtures/webhooks.json
new file mode 100644
index 0000000..be42935
--- /dev/null
+++ b/tests/fixtures/webhooks.json
@@ -0,0 +1,18 @@
+{
+  "data": [
+    {
+      "archived_at": 0,
+      "company_id": "",
+      "created_at": 0,
+      "event_id": "",
+      "format": "",
+      "headers": [],
+      "id": "",
+      "is_deleted": false,
+      "rest_method": "",
+      "target_url": "",
+      "updated_at": 0,
+      "user_id": ""
+    }
+  ]
+}
diff --git a/tests/real_shapes.rs b/tests/real_shapes.rs
new file mode 100644
index 0000000..b024382
--- /dev/null
+++ b/tests/real_shapes.rs
@@ -0,0 +1,227 @@
+//! Decodes fixtures captured from a real server.
+//!
+//! `tests/fixtures/*.json` are written by `examples/capture_shapes.rs` and
+//! hold only key names and JSON types (strings are `""`, numbers `0`, bools
+//! `false`). Mock responses written from the upstream source have been wrong
+//! about the real thing before, so these pin the shapes a server actually
+//! sent. To refresh them, seed a disposable instance with
+//! `examples/seed_sample_data.rs` and re-run the capture.
+//!
+//! Three properties are checked: every fixture decodes into its model
+//! (goal 2), a decode followed by a re-serialise loses no key (goal 1), and no
+//! fixture contains a real value, so a careless capture cannot leak data.
+
+use std::collections::BTreeMap;
+use std::fs;
+use std::path::{Path, PathBuf};
+
+use invoiceninjars::models::*;
+use serde::{de::DeserializeOwned, Serialize};
+use serde_json::Value;
+
+fn dir() -> PathBuf {
+    Path::new(env!("CARGO_MANIFEST_DIR")).join("tests/fixtures")
+}
+
+fn load(name: &str) -> Value {
+    let path = dir().join(format!("{name}.json"));
+    let text = fs::read_to_string(&path).unwrap_or_else(|e| panic!("{}: {e}", path.display()));
+    serde_json::from_str(&text).unwrap_or_else(|e| panic!("{}: {e}", path.display()))
+}
+
+/// The captured row of a list fixture.
+fn row(name: &str) -> Value {
+    load(name)["data"][0].clone()
+}
+
+/// Key paths present in `raw` but absent from `out`. Arrays are compared
+/// through their first element, which is all a fixture keeps.
+fn lost_keys(raw: &Value, out: &Value, prefix: &str, into: &mut Vec<String>) {
+    match (raw, out) {
+        (Value::Object(raw), Value::Object(out)) => {
+            for (key, raw_value) in raw {
+                match out.get(key) {
+                    Some(out_value) => {
+                        lost_keys(raw_value, out_value, &format!("{prefix}.{key}"), into)
+                    }
+                    None => into.push(format!("{prefix}.{key}")),
+                }
+            }
+        }
+        (Value::Array(raw), Value::Array(out)) => {
+            if let (Some(raw), Some(out)) = (raw.first(), out.first()) {
+                lost_keys(raw, out, &format!("{prefix}[]"), into);
+            }
+        }
+        _ => {}
+    }
+}
+
+/// Decodes `raw` as `T`, re-serialises it, and returns problems.
+fn check<T: DeserializeOwned + Serialize>(name: &str, raw: &Value) -> Vec<String> {
+    let typed: T = match serde_json::from_value(raw.clone()) {
+        Ok(typed) => typed,
+        Err(e) => return vec![format!("{name}: does not decode: {e}")],
+    };
+    let out = serde_json::to_value(&typed).expect("serialises");
+    let mut lost = Vec::new();
+    lost_keys(raw, &out, name, &mut lost);
+    lost.into_iter()
+        .filter(|path| !OMITTED_WHEN_EMPTY.contains(&path.as_str()))
+        .map(|path| format!("{path}: key lost on a decode/re-serialise"))
+        .collect()
+}
+
+/// Fields that are deliberately left out of a request when empty, because the
+/// server rejects the empty value (`""` becomes `NULL` on a non-null column,
+/// or fails an `integer` rule). A fixture holds `""` placeholders, so these
+/// show up as absent after a re-serialise. Adding to this list is a decision.
+const OMITTED_WHEN_EMPTY: &[&str] = &[
+    "locations.country_id",
+    "purchase_orders.status_id",
+    "webhooks.format",
+];
+
+/// One fixture per `(file, type)`; the macro also records which files it
+/// covered so a new capture cannot sit untested.
+macro_rules! list_fixtures {
+    ($($file:literal => $ty:ty),+ $(,)?) => {
+        const COVERED_LISTS: &[&str] = &[$($file),+];
+
+        fn check_lists() -> Vec<String> {
+            let mut problems = Vec::new();
+            $( problems.extend(check::<$ty>($file, &row($file))); )+
+            problems
+        }
+    };
+}
+
+list_fixtures! {
+    "activities" => Activity,
+    "clients" => Client,
+    "companies" => Company,
+    "credits" => Credit,
+    "designs" => Design,
+    "documents" => Document,
+    "expense_categories" => ExpenseCategory,
+    "expenses" => Expense,
+    "group_settings" => GroupSetting,
+    "invoices" => Invoice,
+    "locations" => Location,
+    "payment_terms" => PaymentTerm,
+    "payments" => Payment,
+    "products" => Product,
+    "projects" => Project,
+    "purchase_orders" => PurchaseOrder,
+    "quotes" => Quote,
+    "recurring_expenses" => RecurringExpense,
+    "recurring_invoices" => RecurringInvoice,
+    "system_logs" => SystemLog,
+    "tags" => Tag,
+    "task_statuses" => TaskStatus,
+    "tasks" => Task,
+    "tax_rates" => TaxRate,
+    "tokens" => CompanyToken,
+    "users" => User,
+    "vendors" => Vendor,
+    "webhooks" => Webhook,
+}
+
+/// Fixtures that are not a one-row list.
+const COVERED_OTHER: &[&str] = &[
+    "statics",
+    "health_check",
+    "subscription_steps",
+    "activity_feed",
+];
+
+#[test]
+fn every_real_row_decodes_and_loses_no_key() {
+    let problems = check_lists();
+    assert!(
+        problems.is_empty(),
+        "{} problem(s):\n{}",
+        problems.len(),
+        problems.join("\n")
+    );
+}
+
+#[test]
+fn bare_endpoint_fixtures_decode() {
+    let mut problems = Vec::new();
+    problems.extend(check::<Statics>("statics", &load("statics")));
+    problems.extend(check::<HealthCheck>("health_check", &load("health_check")));
+    problems.extend(check::<ActivityFeedEntry>(
+        "activity_feed",
+        &load("activity_feed")["data"][0],
+    ));
+
+    // Keyed by class name on a real server; see `subscription_steps`.
+    let steps: Result<BTreeMap<String, SubscriptionStep>, _> =
+        serde_json::from_value(load("subscription_steps"));
+    match steps {
+        Ok(steps) => assert!(!steps.is_empty(), "the captured steps object is empty"),
+        Err(e) => problems.push(format!("subscription_steps: {e}")),
+    }
+
+    assert!(problems.is_empty(), "{}", problems.join("\n"));
+}
+
+#[test]
+fn every_fixture_file_is_covered_by_a_test() {
+    let mut on_disk: Vec<String> = fs::read_dir(dir())
+        .expect("tests/fixtures exists")
+        .filter_map(|entry| {
+            let path = entry.ok()?.path();
+            (path.extension()? == "json").then(|| path.file_stem()?.to_str().map(String::from))?
+        })
+        .collect();
+    on_disk.sort();
+
+    let mut covered: Vec<String> = COVERED_LISTS
+        .iter()
+        .chain(COVERED_OTHER)
+        .map(|s| s.to_string())
+        .collect();
+    covered.sort();
+
+    assert_eq!(
+        on_disk, covered,
+        "a captured fixture has no test (or a test has no fixture)"
+    );
+}
+
+/// The capture tool replaces every value; this refuses to pass if any
+/// survived, so real data cannot be committed by accident.
+#[test]
+fn fixtures_hold_shapes_and_never_values() {
+    fn walk(value: &Value, at: &str, bad: &mut Vec<String>) {
+        match value {
+            Value::String(s) if !s.is_empty() => bad.push(format!("{at}: string value")),
+            Value::Number(n) if n.as_f64() != Some(0.0) => bad.push(format!("{at}: number value")),
+            Value::Bool(true) => bad.push(format!("{at}: true")),
+            Value::Array(items) => {
+                assert!(items.len() <= 1, "{at}: a fixture keeps one array element");
+                items.iter().for_each(|v| walk(v, &format!("{at}[]"), bad));
+            }
+            Value::Object(map) => map
+                .iter()
+                .for_each(|(k, v)| walk(v, &format!("{at}.{k}"), bad)),
+            _ => {}
+        }
+    }
+
+    let mut bad = Vec::new();
+    for entry in fs::read_dir(dir()).expect("tests/fixtures exists") {
+        let path = entry.unwrap().path();
+        if path.extension().is_some_and(|e| e == "json") {
+            let name = path.file_stem().unwrap().to_string_lossy().to_string();
+            walk(&load(&name), &name, &mut bad);
+        }
+    }
+    assert!(
+        bad.is_empty(),
+        "fixtures contain values:\n{}",
+        bad.join("\n")
+    );
+}