You didn't say if you can weld... If you do, that's a big plus when fabricating brackets, etc. If you don't weld, it may behoove you to take a welding course somewhere and buy a small MIG welder. Yes, it's a bit of an investment, but you'll save the money back in short order compared to shelling out $50+ every time you need someone to stick something together.

That's a great value for $13,200. If you do your own body and paint work, that can save you a pile of $$$. As for upholstery, get some nice seats from the junkyard and you can do the rest of the interior as money allows later. I drove my coupe for a year with the original upholstery on the (Hyundai) seats and a piece of Berber carpet (remnant from the carpet store) on the floor; no door panels and no headliner. Good luck.