Wow, thanks for all the great responses!

I misspoke when I said the windows could be vacuum related. I meant the central door locks, which also don't work.

BoostnBenz: As a matter of fact, the "dead" windows ARE on opposing corners (RF and LR), so that's promising. But I can hear gears grinding inside the RF door, so it may be worse than a fuse. Owner tells me the oil leak is in the fuel distribution unit on the driver's side of the motor. I'm not sure if that's true or even possible, but that's what he said.

dieseldiehard: I definitely want/need cold AC, so I'll try to use R12 if possible. I know a good local AC shop that, as of last year anyway, could still get R12. ($225 for a new compressor actually isn't too bad.) I'll definitely check those engine shocks, too!

LRG: There was no slipping at all in the tranny, it just really slammed hard on the shifts. I like a hard shift, but this was actually a bit uncomfortable. Anyway, it's good to know it may be only vacuum related. Also, there was no hint of lash or crash in the driveline, even with such hard shifts, so that's a good thing, too.

Another thing I noticed on the car is that the fuel in the little clear filter under the hood looked black to me, and I've read that's a sign of algae, which could explain some of the weak accel. problems, right? I'll have to look again to be sure, but since the car may have sat for a long time awaiting auction, this could be the case, no?