When you take out a contract, you decide how many miles a year you will drive.

At the end of the contract, you may have driven a few more miles than the total you agreed.

Extra miles you have driven are charged to you at a rate that's probably between 5p and 10p a mile. Somewhere in that region.

Big expensive cars may be slightly more, per mile.

So, you don't have to restrict how many miles you drive your new car.