Was looking at buying a 2008 Nissan Altima. Sales rep was okahy, but his manager told me they would use Edmunds to value my trade, then the next day when I came back with some numbers figured up on what kind of deal I had in mind, the manager back peddled and started talking about Black Book and cash value. I realize that Black Book is widely used by dealers, but don't bait me by saying you'll go by the higher value guide (Edmunds) then whip out the lowest shooting guide out there-- Black Book. In his defense he did eventually switch to the yellow NADA book, but then he was pointing to the basic valuation before my low mileage odometer amount was factoed in, and treating that basic value as all they would allow. The NADA book showed an add'l $1125 upward adjustment for my miles. All in all it left me with a bad feeling, it felt like they were trying to be too manipulative. So I walked away. I ended up buying a different brand new vehicle at a different dealership a week and half later.