Transom, stringers, fuel tanks, all your fuel lines,.....if the bilge smells bad, has a lot of black slime on the tanks and fails the moisture meter test, you're in for some structural work...spongy deck is also a telltale sign of moisture.....pull a couple of screws from the transom like a trim tab screw and see if water comes out of it....they should all be resealed at this point anyway so I'd check it out if the seller allows it......... window seals, baitwell pump, electronics if they are original and go through the motors as with any boat....shift shafts are common rust out failure that will cost 750-1000 per engine....the boat is 20+ years....expect the unexpected unless someone already has done the repairs before you get it.