I dont think you could set up building frames now. You have to have a name. Building frames for other companies to put a sticker on yeah maybe and i can tell you that happens a lot.
I know an old boy who is in his late seventies that has all the jigs, kit etc and will one day pass them on. He builds about one frame a month for friends.
Jason rourke told me that whilst there is decent money in the top end frames like titanium and 953 say, the others not so much.
You can wreck a frame in 953 and titanium in 2 seconds if your not careful.