We rented a compact car this summer from Europcar at Athens Airport (small Nissan) and were very happy with the price which was significantly cheaper than any of their competitor. (By the way, it is not advisable to rent a car if you don't plan to leave Athens, the city is horribly congested and the local drivers will make you crazy unless you come from Middle East or Sicily).

The car was fine and there were no surprises with their pricing either. Until...it was two weeks after the end of our trip and we found on our bank statement that Europcar Athens billed us no less than 165 Euro - presumably for a damage on the car. Now, you must understand that the garage for drop-off is dark and there was no living soul when we brought the car. We returned the keys at the counter and noone has come to inspect the damage. We are still in touch with their central in Greece but it seems we will just end up paying the money (or rather they will not refund it). Beware of such EuropCar practices and always ask for inspection when picking up and returning the vehicle!