How to set up bitcoin rates API?

Question

API

Hello friends! It is planned to launch a service for selling electronic goods for crypto and other payment systems.
Binding rates for cryptocurrency is carried out through the API of two exchanges bitfinex and bitstamp, choosing the lowest one. For the owner of the service, it is necessary to find and implement a solution for manually adding courses in percentage terms. Example: BTC rate on bitfinex $3600 on bitstamp $3650, the system automatically selects the price for bitfinex and subtracts -3% as it was set by the owner of the resource, gets $3492
While I found a service offering a ready solution https://bitcoinaverage.com, is there alternatives?

Answer 1

Check out this option https://developer.bitaps.com/market