Design and code a 3d shooter game

I'm looking to get a 3d shooter game Requirements are as follows: For designs 1) maps need creating 2) character need creating (3) w/ special abilitys 3) guns need creating 4) enemy's need creating I can give general idea of what I would like the characters, enemies, and guns to look like. For coding 1) I want the user to be able to unlock different maps at different times 2) I want the game to save all user data like ability upgrades 3) guns need to be upgradable 4) enemy's need to get stronger Would like but optional will do later so must know how to add: Pvp Co op on missions and such Budget for such game is around 400 but do keep in mind with success of app i would be going to you for all future upgrades and additional add-ons.