Where should we rent a car after 3 nights in Dublin?

The airport tends to be cheaper (not always however) and pickup/drop off in the same location usually results in the lowest rates.

They also have a larger selection of vehicles available

And all of the companies are in one place.

For my recent trip, I experimented with picking up and dropping off at different locations. I decided there weren't any savings particuarly when you pick up in one spot and drop off at another.

One thing I'm considering for a future trip is to fly in and take the bus to Galway. Then I'd have 2 car free days to go to the Aran Islands. I could pick a car up in Galway and go from there. The bus is much cheaper than a day's cost for the car and I wouldn't have to worry about paying for parking while I'm gone.

I couldn't find any difference in the rates between picking up at the airport vs. picking up out of town. Others may have different experiences.

The other factor might be where you're driving. The airport is close to a major highway, so it's easy to get in and out of, but it's on the north side of town. If you're heading south, you may want to check out Dun Laoghaire.

If you wind up heading south on the M50 from the airport (and you probably will) you need to know that it's a toll road without booths. The cost is a couple of euros and you can pay it by eight pm the next day. After one day, the the fee doubles and after that it goes through the roof.

You pay the toll afterwards at gas stations, newstand, etc. Just look for the sign (it's generally about the size of a license plate and may be buried in the corner of a window or something.

Here's the logo:

http://www.payzone.ie/pages/about-us/contact-us.php

We just got back a few weeks ago, and we rented at the airport, be sure to book here before you go it is much cheaper. We took a taxi to and from. Cost was 30.00 euro into Dublin, 15.00 euro back to the airport, I don't really know why the difference. If you don't want to spend the money on taxi's there are buses that go into Dublin too. The only thing is the airport is really torn up Budget is still at the terminal, but all the other ones are on the other side of the airport. It was very confussng bringing the car back. So give yourself extra time if you would be catching a flight that day. We spent the night at the Radison Airport for a flight the next day. The rental people told us that they were all moving around as the construction continued so it might even been different when you go.

Just got back from Dublin. The airport is the best place as more cars are available to choose from. If you pick up in the city location you will likely have to take what they give you, and then figure out how to drive while in the city. The Airlink buses to and from the airport to city center are 6E each way but are included if you buy a three day Dublin bus pass which you should. It includes the hop on/off bus which is a great way to get around.
Be sure to do your homework before renting in Ireland and get ALL the costs in an email before you go. Insurance costs are high and most Credit Cards don't cover Ireland anymore, and none of them provide for FULL coverage. I have seen sticker shock at the counter and arguments when people get the total rental costs. There are two insurance costs if you want full coverage and zero liability. CDW and Zero excess. Usually the rental companies don't quote all the insurance costs on the websites. You have to email them and demand the TOTAL cost of rental. I just spent 15 days in Ireland and can provide more info if you contact me.

I've tried the Airlink bus, but there was no real place to put my bags because the small area for it was full. Aircoach is also convenient, although more expensive than Airlink, and you can stow your luggage under the bus.

In my experience, the airport has been cheaper than getting the car in town... Plus starting out on a highway/freeway from the airport is much less stressful than driving in Dublin.

By the way, if you are returning to Dublin just to catch a flight, perhaps you could fly home out of Shannon instead? We've flown into Shannon, rented a car, driven all over the place, eventually ending up in Dublin for the flight home. I don't believe there was an extra charge for dropping it off at a different airport.

*** Just read your itinerary in a different post. After Donegal area you could spend the night closer to Shannon Airport, perhaps Ennis (I think your nephew would like it there) or Bunratty (haven't been there but lots of people like it). Then you don't have to drive all the way across the country only to spend the night near Dublin airport.

Thank you for all the replies. We booked a car with Budget at the airport location in Dublin. Our original plan was to fly into Dublin and out of Shannon, but our airline only flies in and out of Dublin. The suggestion on buses to Dublin was very helpful.