Improve CarPass product UX and service flows

tests/test_entries.py

@@ -87,3 +87,44 @@ async def test_stats_do_not_fail_with_insufficient_data(client, auth_headers) ->
 
     assert response.status_code == 200
     assert response.json()["avg_consumption_l_per_100km"] is None
+
+
+@pytest.mark.asyncio
+async def test_expense_crud_and_insurance_allocation(client, auth_headers) -> None:
+    car = (await client.post("/api/cars", headers=auth_headers, json={"name": "Cost car"})).json()
+    created = await client.post(
+        "/api/expenses",
+        headers=auth_headers,
+        json={
+            "car_id": car["id"],
+            "entry_date": "2026-01-01",
+            "category": "insurance",
+            "title": "Insurance",
+            "total_cost": 1200,
+            "period_start": "2026-01-01",
+            "period_end": "2026-12-31",
+            "is_recurring": True,
+        },
+    )
+    assert created.status_code == 201
+    entry_id = created.json()["id"]
+
+    stats = await client.get(
+        f"/api/cars/{car['id']}/stats?date_from=2026-01-01&date_to=2026-01-31",
+        headers=auth_headers,
+    )
+    assert stats.status_code == 200
+    body = stats.json()
+    assert body["expenses_cost"] in {"101.92", "101.93"}
+    assert body["cost_by_category"]["insurance"] in {"101.92", "101.93"}
+
+    patched = await client.patch(
+        f"/api/expenses/{entry_id}",
+        headers=auth_headers,
+        json={"title": "Insurance policy"},
+    )
+    assert patched.status_code == 200
+    assert patched.json()["title"] == "Insurance policy"
+
+    deleted = await client.delete(f"/api/expenses/{entry_id}", headers=auth_headers)
+    assert deleted.status_code == 204