I think kbb is better for private sale and nada is closer to dealer prices (obviously not the case all the time). also depending on what vehicle you are looking at and the area you are in it can be drastically off from actual street (private party prices). i know in the pacific northwest both prices can be thrown out the window for subaru prices. Id also like to know where nada comes up with their value on my 83' 911, not complaining about the $22k+ value they are giving it