It is hard to give you an answer on production costs, legal fees, operating costs without having an idea about the product - which understandably you do not want to give. A couple of suggestions though:

-If you need a CAD drawing go to Outsourcing to Freelance Programmers, Web & Logo Designers, Writers, Illustrators on Elance to get someone to bid on your project
-If it is a physical product look to have it manufactured in Mexico and China right off the start because of the labor scale differences
-Search the US patent database to make sure your product does not have a patent already

Good luck.