Turn a singleplayer simulator into a multiplayer simulator

Hello developers, We are looking for someone who would like to completely transform a singleplayer game into a multiplayer game where players can connect to a game server and play the simulator together. In order for this, they will need to be able to see each other in-game like in real life. Please only bid on this if you are able to work with me, I am not a developer so I am looking for someone who will not get mad if I do not understand something. May I include that this project is a charity project. Lower bids are appreciated. The extra money we have after paying you will be going to the No Kid Hungry charity to help children in need in the new year. Here is a video of what we are expecting once the project is done, this is another person who made a multiplayer version to the game, but ours will be a bit different. Video: [login to view URL] IMPORTANT TO UNDERSTAND: The game is already in stores. We are not building a new game. We are only taking this game and transforming it so that players can play the game together rather than individually. Please bid if interested. Perks to be given to the developer to complete the project. Sincerely,