The seller likely was seeing what a dealer would give and then after hearing the bad news, he decided to sell it at a bargain price to a private party as he would get more that way than from a dealer. Just make sure he has the title or will go with you to where the title is being held, where you can see the payoff is handled and you get the title in hand.
Metro areas are going to have bargain prices when someone is serious about selling their car. There's WAAAAY too much competition to screw around by pricing the car high. Dealers and private parties face an uphill struggle in a crowded market. Cash in and good luck!
Rick