I highly recommend hiring a professional to help with the process. It is like hiring a real estate agent when buying or selling a house. You just need a pro in your corner who is working for you when you are dealing with a large construction project. On a recent project I hired a retired general contractor to help me out. He didn't charge a lot but he helped a ton since he knew who the good subs were, he knew the permitting process and he knew how to navigate the system. A few thousand bucks to the right person can save you a ton of money and frustration down the road.