Additional support for incorporating (at least with simple Delaware based LLC) early; if you build something and can pick up a partner they are far more likely to 'take' any IP generated as a result of products built during the partnership if you are a single, lone wolf contractor. If you get an EIN (employer identification number) and put that on your W9s you can negotiate from a company position for shared IP (as we have - 2 patent applications and the legal work is being paid by our partner...we'd never have been able to close that as two people working together to build a large corporation something).