curl --request POST \
  --url https://api.example.com/api/v1/checkout-sessions \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "customer_id": "<string>",
  "plan_version_id": "<string>",
  "add_ons": [
    {
      "add_on_id": "<string>",
      "customization": {
        "price_entry": {
          "id": "<string>"
        },
        "name": "<string>"
      },
      "quantity": 1
    }
  ],
  "auto_advance_invoices": true,
  "billing_day_anchor": 123,
  "billing_start_date": "2023-12-25",
  "charge_automatically": true,
  "components": {
    "extra_components": [
      {
        "name": "<string>",
        "price_entry": {
          "id": "<string>"
        },
        "product_ref": {
          "id": "<string>"
        }
      }
    ],
    "overridden_components": [
      {
        "component_id": "<string>",
        "name": "<string>",
        "price_entry": {
          "id": "<string>"
        }
      }
    ],
    "parameterized_components": [
      {
        "component_id": "<string>",
        "parameters": {
          "committed_capacity": 1,
          "initial_slot_count": 1
        }
      }
    ],
    "remove_components": [
      "<string>"
    ]
  },
  "coupon_code": "<string>",
  "coupon_ids": [
    "<string>"
  ],
  "end_date": "2023-12-25",
  "expires_in_hours": 1,
  "invoice_memo": "<string>",
  "invoice_threshold": "<string>",
  "metadata": "<unknown>",
  "net_terms": 123,
  "payment_methods_config": {
    "config": {
      "card": {
        "enabled": true
      },
      "direct_debit": {
        "enabled": true
      }
    }
  },
  "purchase_order": "<string>",
  "trial_duration_days": 123
}
'

{
  "session": {
    "created_at": "2023-11-07T05:31:56Z",
    "customer_id": "<string>",
    "id": "<string>",
    "plan_version_id": "<string>",
    "billing_day_anchor": 123,
    "billing_start_date": "2023-12-25",
    "checkout_url": "<string>",
    "completed_at": "2023-11-07T05:31:56Z",
    "coupon_code": "<string>",
    "expires_at": "2023-11-07T05:31:56Z",
    "net_terms": 123,
    "payment_methods_config": {
      "config": {
        "card": {
          "enabled": true
        },
        "direct_debit": {
          "enabled": true
        }
      }
    },
    "subscription_id": "sub_7n42DGM5Tflk9n8mt7Fhc7",
    "trial_duration_days": 123
  }
}