User

{
    "id": "usr_abc123",
    "email": "customer@example.com",
    "externalId": "your_internal_id",
    "firstName": "John",
    "lastName": "Smith",
    "company": "string",
    "billingDetails": {
        "cardLastFour": "4242",
        "cardBrand": "visa"
    },
    "initialSetupComplete": true,
    "createdAt": "2019-08-24T14:15:22.123Z",
    "updatedAt": "2019-08-24T14:15:22.123Z"
}