Rules are
1.Must be 1988 or newer.
2. Must be currently licensed.
3. Must be owned by person buying the new car.
4. Must be drivable.
5. Must get under 18 avg mpg.
If you buy a new car that gets 1-9 mpg better avg mpg you get 3500 against your new car. If your new car gets 10-20 better you get 4500
The 1 billion lasted for 1 week. 1 billion injected directly in to the auto industry. If you figure 4000 as an avg that is 250,000 cars actually sold vs just giving the money to the guys at the top. Inventory sold and money going in to economies where the dealers are. To me it is money much better spent than the Wall street bail out. It is part of the stimulus.
Congress has approved 2 billion more. Money well spent.