Hello, my name is Nelson and I'm a mobile & web developer. I can help you with this project, but in order to give you a proper time and budget estimation we must first define the scope of this REST API.
I would suggest you to describe me how your model would be, and from there we can start drawing the formal specifications of the API. For backend database I would recommend using a mongodb, which I've been working the most lately. If you need it to be an SQL database, that's not a problem either.
Well, I'm available at any time, ust contact me if you're interested.
Best regards
Nelson R. Pérez