curl --request POST \
  --url https://api.revolv3.com/api/Customers/{customerId}/installments \
  --header 'Content-Type: application/json-patch+json' \
  --data '{
  "merchantInstallmentRefId": "1234-5678-9101",
  "billingFrequency": {
    "intervalType": 1,
    "intervalCount": 1
  },
  "startDate": "2025-09-08T00:00:00Z",
  "trialDuration": 0,
  "trialDurationType": 1,
  "taxAddress": {
    "addressId": null,
    "addressLine1": "101 Update Street",
    "addressLine2": null,
    "city": "Irvine",
    "state": "CA",
    "postalCode": "92602",
    "phoneNumber": null,
    "email": null,
    "country": "US"
  },
  "installmentItems": [
    {
      "name": "Billing Plan 1",
      "value": 1000,
      "valueType": "Standard"
    },
    {
      "name": "Billing Plan 2",
      "value": 1200,
      "valueType": "Standard"
    }
  ],
  "downPayment": 200,
  "installmentType": "Amount",
  "installmentValue": 500,
  "paymentMethod": {
    "paymentMethodTypes": [
      1
    ],
    "billingAddress": {
      "addressId": null,
      "addressLine1": "100 Main Street",
      "addressLine2": null,
      "city": "Irvine",
      "state": "CA",
      "postalCode": "92602",
      "phoneNumber": null,
      "email": null,
      "country": "US"
    },
    "creditCard": {
      "paymentAccountNumber": "4111111111111111",
      "expirationDate": "1025",
      "securityCode": null,
      "networkToken": null,
      "processingMethodType": 5
    },
    "ach": null,
    "googlePay": null,
    "applePay": null,
    "merchantPaymentMethodRefId": "payment-method-ref-id_hgays-213-4rf4",
    "billingFirstName": "John",
    "billingLastName": "Doe",
    "billingFullName": null
  },
  "paymentMethodAuthorizationId": null,
  "paymentMethodId": null
}'

{
  "installmentId": 1,
  "customerId": 1,
  "merchantInstallmentRefId": "1234-5678-9101",
  "billingFrequency": {
    "intervalType": 1,
    "intervalCount": 1
  },
  "installmentType": "Amount",
  "installmentValue": 100.5,
  "downPayment": 800.99,
  "initialBillDate": "08-Sep-25",
  "nextBillDate": "08-Oct-25",
  "taxAddress": {
    "addressId": 1,
    "addressLine1": "112 Main Street",
    "addressLine2": null,
    "city": "Irvine",
    "state": "CA",
    "postalCode": "92602",
    "phoneNumber": null,
    "email": null,
    "country": "US"
  },
  "paymentMethodIds": [
    1
  ],
  "installmentItems": [
    {
      "installmentItemId": 1,
      "installmentId": 0,
      "name": "Installment item 1",
      "value": 1001.99,
      "valueType": "Standard"
    }
  ],
  "billingPlans": [
    {
      "installmentBillingPlanId": 1,
      "installmentId": 1,
      "name": "Installment item 1",
      "value": 800.99,
      "startDate": "08-Sep-25",
      "cyclesRemaining": 0,
      "cycleCount": 1,
      "valueType": "Standart"
    },
    {
      "installmentBillingPlanId": 2,
      "installmentId": 1,
      "name": "Installment item 1",
      "value": 100.5,
      "startDate": "08-Sep-25",
      "cyclesRemaining": 1,
      "cycleCount": 1,
      "valueType": "Standart"
    }
  ]
}