My dad has a diamond business in nyc and he is thinking about incorporating in Delaware to save state tax. But I think even if he incorporates in Delaware, he'd have to pay NY state taxes since his business is located in New York. And even if his business is in delaware, I am saying that Delaware will still charge state tax. I see no tax advantage in forming a corporation in Delaware. But my dad thinks otherwise and he says he has to consult an accountant.. But in the mean time, I just want to know if I am right. Am I?