Know it - Don't put a lot of credence in Kelly Blue Book. When I was trading in my GT Cruiser last year I went to quite a few dealers, Kelly trade in report in my hand each time. My car was in excellent condition with really low mileage. Every trade in offer I got was way and I mean way below what the Kelly numbers were. I asked the dealers about this and they said they never (5 different Chrysler dealers) rate a car excellent condition. I think most dealers use another book, someone can correct me here but is it the NADA? And they are constantly dealing with wholesalers for your car. With the number of used cars available these days I think the dealer pretty much has you by the short hairs on a trade in, unless you are trading for something they want off their lot. I've still found the end of the month is the best time to buy.
I've also heard of another service being advertised, sorry I don't recall their name, that will come to you, and buy your car. The ad says they will beat Carmax and Kelly on your car.

Pat