curl --request POST \
  --url https://api.balansas.com/functions/v1/customer-api/fees/preview \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "amount": 123,
  "currency": "<string>",
  "transactionType": "<string>",
  "paymentScheme": "<string>"
}
'

{
  "data": {
    "fee_amount": 2.5,
    "fee_currency": "EUR",
    "schedule_id": "9c8b7a6d-5e4f-4321-8a9b-0c1d2e3f4a5b",
    "schedule_name": "EU SEPA Standard",
    "umbrella_link_id": null,
    "goat_member_code": null,
    "breakdown": {
      "flat_fee": 0.5,
      "percentage_fee": 0.25,
      "percentage_amount": 2,
      "raw_total": 2.5,
      "min_applied": false,
      "max_applied": false
    }
  }
}