The world and his mother buys their car in January. Salesmen cannot walk without falling over someone wanting to give them money. It is a clean slate. New targets, new resolutions etc etc. December however, you cannot drag people into the salesroom to look at a secondhand car. They might want to make 2007 their best year yet sales wise....also gotta clear the decks for all those trade ins come January. Looking at a used car in December is when you will get the better deal.