Autos are much more common in the sedans, so if you are desperate, get an auto and add the $1500ish for a conversion. Watching recent prices, 89 or so seem to go for about $2-3k more for manual. The sedans currently seem to go for $1-2k less than the equivelent coupe (not as much demand), depending on where you get it.
You can just get one for around $10k for 89 fairly stock, but most dealers seem to charge a few $k over that. You're best bet is to import, while its still an option (if you can wait). Otherwise, you're battling the profit takers trying to get a few $ more than they bought it "just because they can".
Headroom in the back would probably be a concern in an r32. Going on my r33, 6ft people wouldn't fit comfortably in the backseat due to the head clearance for long periods. Doubt r32 is any better, if not worse considering they cars have less room overall. You could fit 2 people in the back seat though, but again, not much leg room.