Speaking from experience trying to buy a car remotely (in Florida in fact) - you should see if you can find some local volunteers here to go take a look at it for you. Dealers, and even regular people, are all quite capable of "forgetting" about certain problems with a car.

Furthermore, make the seller demonstrate proof of ownership, best if you can actually talk to the prior owner and confirm transfer from him to the dealer. I've learned the hard way that a dealer can sell you a stolen car and as long as they had good reason to believe that the car was not stolen (and "good reason" ain't much at least in Florida), you will be left holding the bag. Or rather the bill, while the FBI returns the car to the rightful owner. Once you take delivery of the car, its history is all your responsibility and none of the dealer's. You can sue, but you can sue for anything in the US anyway and man is that a hassle compared to the 30 minutes or so upfront that it takes to track down the prior owner and verify that he really sold it to the dealer.

In my case I even went so far as to contact the prior owner, but I did not verify that he had sold it to the dealer that was selling it. In fact, the car had been stolen from him via a forged cashier's check and when I talked to him, he had not yet discovered the forgery (his bank took a whole month before letting him know there was a problem) meanwhile the thief had resold it to the dealer using forged documents and in Florida at least, the dealer had zero responsbility to register the car with any government agency before selling it.