I have a V17... A restore project at best, but it sails... sort of...

The one I bought came with a non-original main sail (from an apollo boat, its close but not the real thing) and no jib. It has a crack in the side of the hull, but it doesn't seem to be leaking. Its not a very big boat, its probably best for 2 people, thought it says it sleeps 4...
HOWEVER, what you should look for, like all fiberglass boats, is look for soft spots by knocking all around, walk around on the deck, it should hold you with minimal bowing in. Also, I've heard of people repainting these with high quality house paint, and for the age, its a better, more cost efficient route.
Also, check the lines, they're relatively cheap, but it'll still cost a couple hundred to rerope the thing...
The keel has a brake wench that won't drop unless you crank it down. It's easy, remember its in the water. Also, there is a nut and bolt in the cabin that locks the keel down.
Its a good boat, but make sure they set it up for you and show you the ropes... pun intended..

Make sure all the rigging is good and the lines and sails are in good condition. Its a good little boat. I'm a little discouraged as I type this cuz I just got back from sailing mine with wife and 3 kids under 6... needless to say, it was pretty frustrating... They're a little young for sailing apparently.