On kbb.com "My Car's Value" is usually in the ballpark if you're listing it privately, although its usually on the upper end of the price scale. Including for Town Cars as because there were a lot of them made, they aren't really a collector's item. Unless they have extremely low mileage (less than 30k miles or so). When I sold a previous car I got around $600 less than KBB said it was worth at the time, and it took a few weeks for someone to buy even at that price. It wasn't a Town Car though, YMMV.
