curl -X GET \
 /checkout/carts/{id} \
 --header "Authorization: Bearer <token>"

{
  "id": "c1b0d0c0-0b0b-4b0b-8b0b-0b0b0b0b0b0b",
  "status": "open",
  "customer": "c1b0d0c0-0b0b-4b0b-8b0b-0b0b0b0b0b0b",
  "customerEmail": {
    "email": "john.doe@example.com",
    "receiverName": "John Doe",
    "type": "TYPE_COMPANY",
    "id": "00000000-0000-0000-0000-000000000000",
    "default": "true"
  },
  "invoiceAddress": {
    "id": "<string>",
    "vatId": "DE123456789",
    "type": "TYPE_DEFAULT",
    "default": "true",
    "status": "active",
    "city": "Berlin",
    "zip": "12345",
    "street": "Musterstraße",
    "houseNumber": "1a",
    "countryCode": "DE",
    "companyName": "ACME Inc.",
    "salutation": "Herr",
    "addition": "c/o John Doe",
    "costCentre": "123456789",
    "firstName": "John",
    "lastName": "Doe"
  },
  "paymentMethod": "c1b0d0c0-0b0b-4b0b-8b0b-0b0b0b0b0b0b",
  "createdAt": "2023-11-07T05:31:56Z",
  "updatedAt": "2023-11-07T05:31:56Z",
  "completedAt": "2023-11-07T05:31:56Z",
  "redirectUrl": "<string>",
  "items": [
    {
      "id": "<string>",
      "product": {
        "type": "product",
        "id": "ad8f1c2c-3b1c-4b0a-8b0a-0b0b0b0b0b0b",
        "name": "Basic",
        "description": "For small teams.",
        "invoiceVisibility": "always",
        "customFields": {
          "field1": "value1",
          "field2": "value2"
        }
      },
      "pricePlan": {
        "type": "flat_fee",
        "currencyCode": "EUR",
        "price": {
          "amount": 123,
          "createdAt": "2021-01-01T00:00:00+00:00",
          "updatedAt": "2021-01-01T00:00:00+00:00",
          "tenantId": "<string>"
        },
        "id": "ad8f1c2c-3b1c-4b0a-8b0a-0b0b0b0b0b0b",
        "applyTrial": true,
        "payInAdvance": true,
        "proRata": true,
        "freeUnits": 1,
        "billingInterval": "1M",
        "showPricePerInterval": "1M"
      },
      "quantity": 1,
      "type": "product",
      "periods": [
        {
          "id": "<string>",
          "contractPeriodCount": 123,
          "contractPeriod": {},
          "cancellationPeriod": {}
        }
      ],
      "createdAt": "2023-11-07T05:31:56Z",
      "updatedAt": "2023-11-07T05:31:56Z"
    }
  ],
  "invoice": {
    "id": "00000000-0000-0000-0000-000000000000",
    "customer": {
      "id": "00000000-0000-0000-0000-000000000000",
      "customerNumber": "CUSTOMER-000",
      "timeZone": "Europe/Berlin",
      "firstName": "John",
      "lastName": "Doe",
      "currencyCode": "EUR",
      "companyName": "Acme Inc.",
      "datevId": "123456789",
      "status": "STATUS_ACTIVE"
    },
    "paymentMethod": {
      "id": "c1a2b3c4-d5e6-4f7a-8b9b-0c1d2e3f4a5b",
      "gatewayName": "wallet",
      "type": "sepa_debit",
      "default": true,
      "status": "active",
      "enabled": true,
      "name": "Visa (4242)",
      "creationDate": "2024-01-15T10:30:00+00:00",
      "expirationDate": "2026-12-31T23:59:59+00:00",
      "card": {
        "brand": "Visa",
        "last4": "4242",
        "expMonth": 12,
        "expYear": 2022,
        "cardHolder": "Max Mustermann"
      },
      "sepaDebit": {
        "iban": "DE8937*********3232",
        "bic": "COBADEFFXXX",
        "mandateReference": "MNDT-2021-123456",
        "signingDate": "2021-01-01T00:00:00+00:00"
      },
      "paypal": {
        "email": "max@mustermann.de",
        "billingAgreementId": "I-1J5gqz2eZvKYlo2C2X2X2X2X"
      }
    },
    "type": "TYPE_INVOICE",
    "currencyCode": "EUR",
    "number": "RE-0000000001",
    "status": "STATUS_DRAFT",
    "finalizationDate": "2023-11-07T05:31:56Z",
    "dueDate": "2023-11-07T05:31:56Z",
    "dunningLevel": 123,
    "dunningStatus": "none",
    "payDate": "2023-11-07T05:31:56Z",
    "invoiceAddress": "<unknown>",
    "internalNote": "This invoice is with a special discount.",
    "netAmount": {},
    "grossAmount": {},
    "taxAmount": {},
    "customFields": {
      "field1": "value1",
      "field2": "value2"
    },
    "unpaidAmount": {}
  },
  "subscription": {
    "id": "ad8f1c2c-3b1c-4b0a-8b0a-0b0b0b0b0b0b",
    "externalId": "<string>",
    "number": "S-00000001",
    "name": "Fitness M",
    "billingGroup": {},
    "periods": [
      {
        "id": "<string>",
        "contractPeriodCount": 123,
        "contractPeriod": {},
        "cancellationPeriod": {}
      }
    ],
    "status": "active",
    "activatedAt": "2021-01-01T00:00:00+00:00",
    "poNumber": "PO-00000001",
    "contractDetails": {
      "contractStart": "2023-11-07T05:31:56Z",
      "contractEnd": "2023-11-07T05:31:56Z"
    },
    "trialEndsOn": "2021-01-01T00:00:00+00:00",
    "customFields": {
      "field1": "value1",
      "field2": "value2"
    },
    "nextBillingDate": "2023-11-07T05:31:56Z",
    "lastBillingAt": "2023-11-07T05:31:56Z",
    "partner": {
      "id": "ad8f7e7d-3b3b-4b3b-8b3b-3b3b3b3b3b3b",
      "name": "John Doe",
      "number": "123456",
      "email": "partner@example.com"
    }
  },
  "metadata": {
    "yourKey": "value"
  },
  "transactions": [
    {
      "id": "ad8f1c2c-3b1c-4b0a-8b0a-0b0b0b0b0b0b",
      "type": "payment",
      "status": "new",
      "description": "Payment for invoice #123",
      "documentNumber": "123456789",
      "currencyCode": "EUR",
      "amount": 500,
      "refundedAmount": 123,
      "chargedAmount": 500,
      "feeAmount": 50,
      "createdAt": "2023-11-07T05:31:56Z",
      "paidAt": "2023-11-07T05:31:56Z"
    }
  ]
}