im considering buying one soon and i was wondering if there were any common problems to look out for. thanks

The only thing that comes to mind right off would be the timing belt. I have heard that the 3rd gens tend to go through those a little quicker than average. I would say a lot of different things would need to be replaced on a car that age such as belts, hoses, sensors along with the usual wear-n-tear items (brakes, roters, clutch, etc.) What trim are you looking to get? If you are looking at an SE, I would highly recomend getting a '92-'94. The engine was bumped up on those models from 160 hp to 190, plus Nissan did a nice face lift on them at that time. And, they got those nifty soft spoilers!

1. 89-92 Automatics go bad often2. Exhaust manifold studs break often3. 92-94 SE VTC's go bad often4. Rubber fuel hoses for fuel rail in VG's crack allowing fuel to leak5. Bose radios/amps/speakers go bad oftenThose are the major items but there are more minor problems.