Kosmos Car Hire In Athens Greece is a car rental company based in Athens, which has been in the car hire business since 1977. Our company takes pride in its hire car fleet, which includes 2,500 hire cars of various sizes throughout Greece. Clients have a choice of mini vans, open-air cars and luxury cars, with either an automatic or a stick-shift transmission. All rental cars are models of the past two years and 40% of the rent a car fleet is renewed every year. Long-term car leasing programs are also offered by Kosmos Car Hire.