Android bingo type game

I am looking for a developer to help assist in building a new Android game, based on a bingo concept, but with a few quirks and perks which make it novel and fun. The game itself is simple and I think will be well received by the community. There would be two versions of this game made, a free version with ads and no leaderboard function with only 1 board available to play on with access to half the possible DLC of the paid version, and a paid version with leaderboard functionality and full access to all DLC boards (about 10 in total, all of which are being created by a graphic designer currently). Looking to have the nuts and bolts of this game's Java programming developed for about 500 dollars if possible. We will need the function to create a user profile for the leaderboard on the paid version, as well as the ability for the player to switch boards at any time, as they unlock them through purchase. A store function would be helpful too, so they can get to the DLC at any time. Winning bidder will need to sign an NDA before any more details are given regarding the rules or the game itself.