NFC/MIFARE card implementation for payments

Hi, We're building a contactless payments application. Need a simple application that will provide an ID + some randomness. My partner will read it with their terminals and send the value to me via an API. Thinking of using MIFARE DESFire Light or MIFARE DESFire EV3. Need help setting up the cards and writing documentation to my partner for integration. Need to execute this in 2 weeks max. Thanks! Alejandro