make smart cars the only form of under 21 transport, can only carry one passenger so no showing of with a car full of youngsters,
fit limiters and trackers. job done. but offer the cheaper residuals.
one of my sixth formers has an insurance policy which fits a tracker to the car, so it knows if he speeds through areas or breaks the limits, it also limits him to 6000 a year mileage, and clcks that too. if he breaks the speed limit i think it even contacts his parents.