where's it been and has it had any maintenance...check suspension completely, get it on a lift and check the rubber gaskets on the control arms, air bags, oil pan for rust int he "this spot collects water so it's gonna rust spot", pull back the trunk carpet and check the rear shock mounts and rubber gaskets, open both doors bend over and visually inspect under the rubber molding for rust and run your hand along the bottom feeling for rust, run a systems check,...then of course all your normal things: check oil remove cap look in to see if all pretty clean, check trannie fluid, give /af a good eye ball for proper color, road test, lock up brakes, feel for rotor wear, run hard to feel if all plugs are hitting, drive long enough to be able to feel if trannie shudders...(even the slighest shutter and your looking at 2g's in 1 yr!)
I just got done looking at a 93 - looked great, but had a lot of hidden surprises... when your buying on older one, you gotta keep in mind, many of the parts on a Mark were meant to be maintenanced, if the mlg didn't make it to the mlg required for maintenance, then the rubber your looking at is 17yrs old and, if driven daily (which obvioulsy has not been the case since the mlg is so low), will need replaced shortly after you uby it.
actually it's best to take a check list with you and just go down it as you inspect... he's asking a pretty penny for 93, especially if it's a northern state Mark