I've been in auto business for over 20 yrs, more than half with dealers both new and used. Typically, money starts to dry up around the second week of December. By January you're sometimes wondering what you're going to do to make a buck. Beginning around the last week in February the tax returns start rolling in and people come in spending like they've just hit an oil well. That usually lasts through the end of April into May. I spent almost three years at a specialized dealership for collector cars. The goal was to make enough by the end of April to carry the rest of the year. They'd usually do it, too.

Personally I've found that the best time to sell anything is when my wife is involved. She seems to have a knack for finding people willing to part with money. That's always made me wonder what she was thinking when she met me...