I booked my car with Greeka.com and I picked up my car in an agency of Kefalonia. I rented a car (Hyundai Getz) for 7 days. I got the car from Kefalonia airport and delivered it at the same point. I generally got satisfied with the service and the people were welcoming and professional. I faced no problem with the car or the roads, which were in quite a good condition.
Alex.P