curl --request POST \
  --url https://api.fairground.fi/order_service.v1.OrderService/GetEstimatedFees \
  --header 'Authorization: Bearer <token>' \
  --header 'Connect-Protocol-Version: <connect-protocol-version>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "marketId": 123,
  "margin": 123,
  "leverage": 123,
  "size": 123,
  "price": 123
}
'

{
  "fees": 123
}