I have read many horror stories regarding renting cars in Ireland. I must say our recent experience with Dan Dooley's at the Dublin Airport was completely excellent in every way -- and far exceeded our expectations. We had reserved a compact diesel with manual transmission online at dandooley.ie. We were on a very tight budget, so every penny counted. We declined the CDW and Super CDW coverage -- more on that later.
At the car rental facility, to which we were quickly shuttled, our assistant Steve took us out to the car, which was a 2013 Renault Megane TDI. He showed me "the ropes" in terms of operating a diesel with keyless remote. Then he asked if I'd ever driven on the left side of the road. When I replied "No", he spent some time going through various pointers, encouraged me to drive the one-way loop around the facility a few times to get accustomed to driving on the right hand side of the car, and also recommended not trying to drive into Dublin right away. All his advice was excellent.
We had not expected the car to be air conditioned, because that wasn't one of the features listed for our rental class, but it was indeed. We didn't need it much, but it was nice to have, especially after trying to dry off after rains and swimming.
The car functioned flawlessly. It ran quietly and seemingly smoke-free. It took awhile to get used to shifting the manual transmission with my left hand (I frankly hadn't even thought about that issue), and I stalled it out a few times thinking I was in first gear when actually in third. It had very good acceleration off the line though it was a tad lackluster on the high end when passing. Our fuel economy over 12 days of driving both city and highway ranged between 4.2 and 4.9 liters per 100 kg. Do the math and you get 48 to 56 mpg! Contrary to most areas in the US, diesel is actually cheaper in Ireland than unleaded. Highly recommend renting a diesel there.
Back to the actual rental process, though. You have to do your homework ahead of time or you will be shocked when you get to the rental counter -- and that goes for ANY Irish car rental agency. You can choose to pay for CDW, like here in the USA, or the Super CDW, which also covers damage to tires and windshields -- the standard CDW does not.
Or you can waive the CDW entirely, IF... You can waive the CDW only if you pay for the rental with a MasterCard or Visa issued on a USA bank. Your credit card MUST feature CDW insurance coverage that includes Ireland (which most exclude) and you MUST have a letter from MasterCard or Visa stating that their CDW coverage will be in effect during the dates of your car rental. You will also be charged a 25 euro fee for waiving the CDW coverage.
You must also have Irish personal liability coverage, but that is included in Dan Dooley's rate quotes.
But then there is this term "Excess". Excess is a deposit that Irish car rental agencies have instituted to reduce their liabilities for the most common damages their cars are returned with. It allows them to get paid immediately for the damage without involving insurance companies. For example, you waive the CDW coverage and you bring the car back with a missing side-view mirror (not uncommon in Ireland). They will deduct the cost to replace the mirror from your excess, and you will haggle with MasterCard or Visa about getting reimbursed.
You will be assessed an excess deposit regardless of your CDW coverage. The amount varies with the value of the car. Our Renault Megane was assessed at 2200 euros. We could have given them a deposit of 2200 euros up front or we could pay an "excess fee" to reduce the amount of the deposit, including all the way to zero deposit. Whatever fee you pay is gone -- it belongs to the rental agency. Any excess deposit you leave with them will be returned -- minus the cost of any damages.
You can also choose to waive the Excess entirely -- sort of. This is where your credit card, and specifically your credit card account, comes into play again. If you choose to waive the Excess, they will place a hold on your card amounting to the entire amount of the Excess -- about $3,000 in our case. If you don't have an adequate credit limit on your card before traveling, you will be paying an Excess fee. I have heard this can amount to the full cost of your rental -- or more. Or worse, if you waive the fee, they place the hold on your account, and then you find out your card is getting rejected because you've exceeded your credit limit.
We chose to waive the excess, but we also have a $10k limit on our card and we paid off the entire balance on the card the day before we left the States.
The young lady at Dan Dooley's car rental counter in the Dublin Terminal carefully explained the excess/hold business to me so there would not be any misunderstanding. This is one of the key things I like about Dan Dooley's: they do not try to force you into paying extra over and above their quote. Their quote includes everything, and if you reserve online, they explain a lot of what I've explained above so there are no surprises.
So again, our entire experience was excellent. I believe we saved a lot of money by going with Dan Dooley's and we got a great car. I was very careful while driving and we fortunately had no mishaps. Not to say it couldn't have happened, but I believe our risk was small and would have likely only involved us in numerous hassles over the CDW coverage. Choose what your comfortable with, but just be aware: Irish car rental base charges are very inexpensive, but if you opt for full insurance, expect to pay 2 or 3 times the base charge.