Sounds like a great project! You are correct to be concerned about this starting and ending the right way. My best advice to you, would be to enlist the help of an architect. Residential architects are a terrific resouce to help with laying out the specs of a project. This way, when it comes to hiring a contractor, you already know exactly what the project will entail and are in a better position to negotiate labor costs, scope of project, time frame, budget and other details.
An architect can also help with planning for tricky spaces as well as specific rooms like kitchens and baths. And have good advice on proceeding with any work that requires structural consideration, including a check by an engineer. A good place to start would be with professional organizations like the American Institute of Architects, which offers specific certifications in many areas to its members.
Best of luck with this project and please be sure to share the finished product.