I would say that assuming someone that can build and cover a kit in 20-30 hours and do a good job, well.... is not human! I just built a MidStar 40 and probably averaged 2-3 hrs a night on it! IT TOOK ME FOUR MONTHS. Suck it up pay the bill and lesson learned! You should have settled on a total price to build it rather than an hourly rate! Just my .02!