curl --request GET \
  --url https://api-eu.flexportal.io/v1/subscriptions/{subscriptionId} \
  --header 'Authorization: Bearer <token>' \
  --header 'Tenant-ID: <tenant-id>'

{
  "rentalId": "<string>",
  "tenantId": "<string>",
  "assetSerialNumber": "<string>",
  "customerId": "<string>",
  "sku": "<string>",
  "productName": "<string>",
  "monthlyAmount": 123,
  "currency": "<string>",
  "status": "active",
  "originalContractLength": 123,
  "contractLength": 123,
  "startDate": "<string>",
  "orderId": "<string>",
  "customerEmail": "<string>",
  "customerName": "<string>",
  "createdAt": "<string>",
  "updatedAt": "<string>",
  "createdBy": "<string>",
  "billingGroupId": "<string>",
  "endDate": "<string>",
  "nextBillingDate": "<string>",
  "lastModifiedDate": "<string>",
  "extensionHistory": [
    {
      "extensionMonths": 60,
      "oldContractLength": 60,
      "newContractLength": 60,
      "oldMonthlyAmount": 1,
      "newMonthlyAmount": 1,
      "extendedBy": {
        "userId": "<string>",
        "email": "<string>",
        "displayName": "<string>",
        "role": "<string>",
        "memberId": "<string>"
      },
      "oldEndDate": "<string>",
      "newEndDate": "<string>",
      "extendedAt": "<string>",
      "reason": "<string>",
      "notes": "<string>"
    }
  ],
  "actualMonthsRented": 123,
  "monthsSaved": 123,
  "deviceRrp": 123,
  "rrpCaptureDate": "<string>",
  "rrpSource": "custom_field",
  "replacementHistory": [
    {
      "oldSerialNumber": "<string>",
      "newSerialNumber": "<string>",
      "reason": "<string>",
      "replacedBy": {
        "userId": "<string>",
        "email": "<string>",
        "displayName": "<string>",
        "role": "<string>",
        "memberId": "<string>"
      },
      "replacedAt": "<string>",
      "damageAssessment": "<string>",
      "insuranceClaim": true,
      "notes": "<string>"
    }
  ],
  "buyoutDetails": {
    "buyoutPrice": 1,
    "calculationMethod": "auto_calculated",
    "reason": "customer_request",
    "processedBy": {
      "userId": "<string>",
      "email": "<string>",
      "displayName": "<string>",
      "role": "<string>",
      "memberId": "<string>"
    },
    "buyoutDate": "<string>",
    "calculationBreakdown": {
      "remainingMonths": 60,
      "remainingMonthsPayment": 1,
      "rrpPercentage": 123,
      "rrpAmount": 1,
      "flatFee": 1
    },
    "notes": "<string>"
  },
  "earlyReturnDetails": {
    "fee": 1,
    "feeWaived": true,
    "calculationMethod": "auto_calculated",
    "returnCondition": "excellent",
    "reason": "<string>",
    "processedBy": {
      "userId": "<string>",
      "email": "<string>",
      "displayName": "<string>",
      "role": "<string>",
      "memberId": "<string>"
    },
    "returnedAt": "<string>",
    "calculationBreakdown": {
      "method": "remaining_months",
      "remainingMonths": 60,
      "gracePeriodApplied": true,
      "daysFromStart": 1825
    },
    "damageAssessment": "<string>",
    "notes": "<string>"
  },
  "upgradeFromRentalId": "<string>",
  "customFields": {},
  "notes": "<string>"
}