I just thought I'd post a data point about the (non-tesla) trade-in program. This is a deal whereby the delivery specialist can pick up your old car and take it away when delivering your new Model S. It's done with a deal with Autonation Direct. I believe it's only in California, but I'm not sure about that.
I just got rid of a Mercedes CLK 63 AMG convertible. Wonderful car, but for some reason I almost never drive it, since the Roadster is just too much fun. I wanted to do the trade-in thing. So a week before the (scheduled) delivery of the Model S, I went on the Autonation Direct web site and in about 10 minutes, supplying the VIN and options and answering questions, then waiting a day or so, I got a certificate saying they'd buy it for $27.5k. This was conditional on someone checking that the car matched the description, but I believe that's what they are trusting the Tesla delivery specialist to do. The certificate was good for 10 days and no more than 250 miles different than described. We were going to drive up to Fremont to take factory delivery, so I had to guess the miles.
I also tried AutoTrader.com, as the Kelly Blue Book website led to them. The offer was a bit less, $26.5k IIRC. (Blue Book was about $36k.)
(Un)fortunately delivery was delayed, and the certificate expired unused. But in the meantime I was getting lots of phone calls from the headquarters of Autonation in Florida, wanting to get their hands on the car. I figured it must be worth more than they were offering. Well, of course, since they have to make a profit, but you know what I mean.
So when delivery was again getting close, I got another certificate from Autonation Direct, but told Peter (our Delivery Specialist) that I was going to look around a bit more. He said "Gee, I'd hate to have to change the delivery contract again, it might delay delivery", and since paying for the Model S was not contingent on getting the trade-in, I said "OK, forget the trade-in then." Peter said "You might also try CarMax."
So I found the local CarMax, and made an appointment to go in and have the car appraised. I was running early for the appointment, and the Merc dealer I bought the car from 5 years ago was just down the road, so I dropped in. The guy there was mumbling something about "absolute maximum $28k, but we probably have to fix the brakes, that's about $5k, but maybe not, make an appointment to leave the car with us for a day for us to check everything out."
I went up to CarMax, and in about 20 minutes had a certificate in hand for $31k. Went back later that evening (they're open until 9pm!) and swapped the car for a bank draft. That took another 20 minutes or so. Very painless, and a much better price. Got a call from the Mercedes guy later, and when I said I'd been to CarMax, he said "Good for you... go with them."
Someone is getting a great deal on a fantastic used Mercedes. .