Build me a video game selling and downloading app.

I want to create a program similar to steam. Users will be able to purchase video games and download them through the program. Users will have accounts, friends, and a game library. There will be features that will differentiate it from steam. Developers will be able to upload their games and sell them upon approval, and players will be able to purchase the games and download them. I will explain the difference between this and steam once a programmer is selected. It has features that will draw users away from steam and to this platform. I do not yet have a name for it. However, I believe that with the right programmers, this could become big. I currently have nothing coded for this project. I do not have the funds to pay a lot of money at the moment, however, the chosen developer will receive a portion of the money made through this program. I am looking for a long term coder.