Not sure. If there's an army surplus Abrams on the market, it'll probably have its turret screwed up and engine block shot to hell, so it'll be relatively cheap (ten thousand dollarish, I'd imagine), and would only take a few months to restore.
The jumper, well, I'm trying out a design since I can't afford a car, so that should tell you the price range. There's no guarantee that it'd work, and I haven't worked out a power source yet, so it may not even be worth that. Still, I'll sell you a copy of the blueprints for, oh, say, $2500. That should take care of the fan system for me, and that's all I really need at this point. Problem is, it DOES cost moeny to make, and I'm skint. Something like $500 in life savings, $30 pocket change, and that's it. Not even enough for a housing.