I see in the comment section that he has lower it from $20,000. I personally think there most be some kind of exhaust leak, because he is definately not right in the brain if he thinks is going to get that kind of money. Don't get me wrong it looks like a very nice car but he doesn't have a clue.
Maybe $5000 if on site inspection checks out. I bet idf it's all original with that mileage, the steering and suspension has some parts that need to be replaced. Among other things.