I booked on line with rental cars.com for my trip from Dublin to Killarney. I did not realize that they are not a rental company but a booking agent that then sells the booking to a rental car company. When I arrived a Thirty to pick up my car with my prepaid voucher, I was told that the insurance I purchased, at 17 Euros/day, was only with rental cars.com and if I wanted to be covered with Thirty I would have to purchase their insurance as well as be charged the excess. The excess is 1200 Euros charged to your credit card at the time of rental--not a credit card hold, but an actual charge. The rep stated that should the car be damaged (flat tire, broken windshield, etc.which is not covered by the 16 Euro a day additional insurance I needed to purchase) then they would keep the amount to pay for the damage. I was very concerned at what rate they would be charging me to fix the tire. I cancelled my reservation and went to another agency. The Dublin airport has Europcar affiliated with National in USA, Avis, Budget, and several other internationally recognized companies to rent from directly. Rentalcars.com stated that since I cancelled at the time of pickup that I will be charged a cancellation fee of THE TOTAL AMOUNT OF THE RENTAL 145 Euros! I am currently disputing this with rentalcars.com and my credit card company. Avoid the middle man; book directly with car rental companies. BTW navigation rental worked very well even in foggy weather. Personally I am very glad we chose to drive. For half the cost of a tour we saw everything we wanted. We left from Dublin and drove to Cliffs of Mohr by way of Limerick then down to Killarney--it was a long day but the roads where good and easy to drive. The next day we drove the Ring of Kerry and Skellig Ring this also had good roads, great scenery, and like being able to stop where and when we wanted. Only problem was a wrong turn off the Valencia Island bridge--our fault-- which put us on a gravel road about the width of a picnic table-I kid not--going straight up a mountain while the fog was rolling in. It was so steep when I finally got turned around almost stalled in 1st gear-yikes. But I lived to tell the tell and would still recommend it to others. The car was economy with very comfortable seats and prefect for 2 people--Hundi i20. Hope this saves some the hassle of a bad rental experience.