Thanks so much for the advice... The SJ21 does have known issues with the deck (water damage) and keel. I found an accredited marine surveyor (SAM) who is only about 75 minutes from Indianapolis and therefore much more reasonable in price. I've decided to go that route as I don't want to be stuck with a major hidden problem. Although $3500 - 4000 isn't much for a sail boat, it means a bit to me, so the $300 or so spent on the surveyor makes sense for peace of mind.
If it is that close you might be able to leave a deposit with the owner, and trailer it to the survey. That might save you some money.