I recently bought an 1978 pearson 30. Paid $8500 and put another $8K into it to replace the atomic four with another atomic four. New running rigging and roller furler, good sails, average cosmetics on the outside, gps depth/knot meter, stereo, very well maintained and lots of extras. I agree with everything southernsmoke said. I bought a cheap, well appointed, old boat which was already maximally depreciated. I single hand this boat almost all the time so I would make sure everything on your boat comes back to the cockpit for single handing. I would have rented if there were more options in this area. If I decide that i'm not really into sailing I can sell this boat and lose very little. Keep in mind that almost all the boats in the marina never leave the marina (you don't want too much money rotting in the water). Also, my wife saw the boat, asked when we could sail to mexico, motored around on it once and will never leave the marina on the boat again!!
I wouldn't buy a boat again with a bad engine, too much hassel. Take your time, look, compare, read, dream about it, and make sure it has everything you want (don't plan on adding anything after you buy it, too expensive.) Some think dreaming is half of sailing anyhow!