Most local dealers said they are participating in the "Cash for Clunkers" program, or the Car Allowance Rebate System. The $1 billion government program, signed into law earlier this year, offers $3,500 to $4,500 credit toward the purchase or lease of a new vehicle with the trade in of an older, less efficient vehicle. From the U.S. Department of Transportation:• Your vehicle must be less than 25 years old on the trade-in date • Only purchase or lease of new vehicles qualify • Generally, trade-in vehicles must get 18 or less MPG (some very large pick-up trucks and cargo vans have different