sounds to me like you really don't want to sell it to him, but looking for some good way to tell him? My son in law is always asking about different projects, I tell him that I don't mind helping him some but, I have enough of my own major projects and he needs to be able to have a place, tools, and time etc to do it on his own. I'll help if he gets stuck, but not come over and do it for him or even be with him the whole time.