you don't see your vehicle get hurt but every time you run into a car or get shot it deducts credits from you, so taking out the cops isn't what you should unless you have a weapon
smasher and rockets are best. my fav strategy is drive in a straight line and just shoot rockets repeatedly (hold down space bar) nothing will get in front of you!
it adds the numbers when your combo is done so if you just end a mission with +40,000 it won't add it because the the combo hasn't finished, or so the computer thinks
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