The rental agencies determine the rules for that. Most rental companies will not rent to anyone under the age of 25. Some will rent to people 21 to 24 years old, but charge a premium rate. The only time I have ever heard of a rental car company renting to an 18-year old is to a member of the military.
1 The lens is a soft, transparent, spherical structure that is suspended within the eye, just behind the pupil. 2  The lens is responsible for focusing light coming in through the pupil onto the retina in the back of the eye.
Etymology: L, pupa, doll. a circular opening in the iris of the eye, located slightly to the nasal side of the center of the iris. Like the iris, the pupil lies posterior to the cornea and the anterior chamber of the eye and is anterior to the lens. Its diameter changes with contraction and relaxation of the muscular fibers of the iris as the eye responds to changes in light, emotional states, and autonomic stimulation.