I would recommend going over the boat with an eye for the things that would be costly to replace or repair. Look at the sails, main beam, trampoline, bottom of the hulls, rudders, centerboards and mast. If you see things that are bent, cracked, ripped or broken you want to consider the repair/replacement cost of these items in the sale price of the boat. Replacement of lines, bolts, split rings etc. and standing rigging aren't a big deal. I know this sounds obvious but you would be surprised what it costs to rejuvenate a cat part for part.