Hi James,
This has to be a shorter answer than I put on your other thread (compare/contrast the Wave & H14). If you buy a used Wave, check for soundness of the hulls--unlikely to be a problem and good condition of the rigging. Be aware that the rigging on a Wave often seems sloppier than on the 14; this is intentional and the fact that the leeward shroud line (the mast side-stay) seems loose isn't necessarily bad. The newer shroud's hook to the hulls with a little clamp kind of arrangement that has a hole for a ring to lock them on--if you don't have that hole, I recommend new shrouds or taping the clamps with electrical tape. We did have the leeward shroud come unhooked once with our old shrouds that didn't take the locking ring--way more exiting than we needed; fortunately, my wife was with me and got it back on without a problem--I shudder to think if it had been one of the kids with me or just me....
On the 14, the main problem is likely to be soft spots in the hulls. The fiberglass shell tends to delaminate from the foam core and although this is repairable if it's not too bad (there's various techniques discussed here and in other forums), it's a pain to deal with if you have a lot of them or they're severe.
Be sure to also check the bottom of the hulls on the 14 as they can get pretty worn down depending upon how they're handled and what they've been dragged over or scraped on. You may need to apply another layer of fiberglass cloth to the bottom to fix it up.
Checking for sound rigging applies too (except that the 14 doesn't attach the lower end of the shrouds in the same way so that particular issue won't come up).
Good luck!