Sir,
I'm a professional game developer, expert in unity3D development. For the past years, I've improved my skills in this field, mastering many algorithms and technics used in game developement.
A developer needs methods to be efficient, so here is how I work : I develop small modules that are tested and documented for you to easily maintain the code. In addition, when I'll finish the job, I'll write a full documentation file to explain what has been done. During all the job progress, I'll stay in touch with you, so that you can tell me if that's what you expect, I'll adapt my work in real time to your needs.
Depending on what you expect from your game, I'll tell you how much time I need to complete it. For a standard 3D action game, if you provide me all the art and design, I'll be able to complete it within 10 days.
I'm a gamer, and a passionate game developper, that's why I'd be glad to work with you on your project, so I look forward to hear from your response.
Regards