I want my users to deposit crypto into the website for credits, but the biggest issue is getting the input address (the user's address). How can I identify the sender from the transaction (since there can be multiple inputs) as well as the amount they sent (since there can be multiple outputs)?
A lot of services offer payment forwarding but they all seem the same but have different fees, some requiring a subscription of over 80$ a month (cryptoapis, blockcypher) or some having service fees (apirone, bitapis, etc). However they all seem to be the same so I don't understand the price differences, in fact some of them are downright identical (cryptoapis & blockcypher). How would I make my own, and would it be worth it for a start up?