curl --request POST \
  --url https://api.pingproxies.com/1.0/public/user/checkout/quote \
  --header 'Content-Type: <content-type>' \
  --header 'X-API-Private-Key: <api-key>' \
  --header 'X-API-Public-Key: <api-key>' \
  --data '{
  "country_id": "gb",
  "cycle_interval": "month",
  "cycle_interval_count": 1,
  "product_code": "isp_gb",
  "product_protocol": "ipv4",
  "product_type": "isp",
  "promotional_code": "NEWYEAR2025",
  "quantity": 1,
  "service_fulfillment_filter": {
    "asn_id": 7018
  }
}'

{
  "data": {
    "before_discount_total": 350,
    "credit_balance": 99050,
    "credit_only_checkout": true,
    "customer_credit_balance_applied": true,
    "customer_credit_balance_applied_amount": 350,
    "discount": 0,
    "discounted": false,
    "invalid_reason": "null",
    "is_top_up": false,
    "is_valid": true,
    "line_items": [
      {
        "item_country_id": "gb",
        "item_name": "Static Residential ISP Proxies [GB]",
        "item_per_unit_amount": 350,
        "item_price_id": "price_1QJx2DB2BUlqim5lxmO3aT2v",
        "item_price_type": "recurring",
        "item_quantity": 1,
        "item_total": 350,
        "item_type": "isp",
        "service_fulfillment_filter": {}
      }
    ],
    "promotional_code": "null",
    "promotional_code_id": "null",
    "top_up_amount": 0,
    "total": 350,
    "total_after_applied_credit": 0
  },
  "message": "Quote generated successfully."
}