I wouldn't do blueboook value either, because I mean it's a freaking type R. I don't care what anybody says, you cannot put that car together for a measly 4630.00 U.S. Or Canadian. Not with that suspension work or whatnot. The best thing to do is to price it out as if you were going to build a car like that and take off money here and there, since he has obviously used it. Also having ac is a big plus, but that's only for me since I live in the desert. I've payed well over 8 grand on my 93 coupe, and it has a stock b16, kyb agx struts, rear disc swap, poly bushings all the way around, lsd, lightweight flywheel, and rotas. I would refuse to let it go for 4630. Fuck that, I don't care how much blue book says. I obviously wouldn't sell it for no 8k, but 4630 would be laughable.
A personal loan would be the best way to go since something that old is hard to finance, but be aware that you will pay a interest rate.