[damncabbage]

Everything you've said on this post leads to a big, flashing, neon sign saying "DON'T DO IT, MAN".

It's your own choice, but if you can't depend on him, doesn't have the skills in the areas he'd need to have, and seemingly wants to muscle in because he's watched a movie, then I think it's probably better if you find a way to decline without being too rude about it.

Maybe help brainstorm his own idea he can run with, if only to be supportive?