泰晤士河畔里士满rules state drivers must be 21 and overbefore they canrent a car.However, young drivers will be subject toan extra chargeand some restrictions on choice.Many companies imposea daily young renter feein addition tothe standard rental rate.This covers the extra riskof damage or accident.While many car classes(like mid-size and compact)are available to young renters,restrictions usually apply tospecialty cars.