bozo, while I admire your thoughts you are going to lose a lot of $$$ trading in your X5. The $$$ you lose, plus the purchase price of the used vehicle (plus any automatic depreciation once you drive it off the lot) really makes an idea like this not worth it. Just my $.02, I understand your situation.

Why not buy a 'beater'? I drive a Pontiac around the city and it's perfect for the traffic and commute. It sips 87 and gets 30mpg on the highway.