Pros: After extensive research on renting a car in Ireland for people under 25... Hertz seemed like the best option.. No where on their site did it say they couldn't rent to you if you were under 25.. Nor that was going to be a problem when we arrived. Even reserved the car online, but still didn't ask my age, or say anything about them requiring you to be 25. I've renting many cars, some in Iceland, Thiland, Nepal, Laos, always been fine.. Usually just charged an extra amount per day because you are 25. After tons of trouble at the London airport, we land in Shannon, Ireland... And Hertz wouldn't rent us car because we were under 25. In fact, none of the 7 car rental places would rent to us..
So, I would say it would be nice to know that a head of time. It's very frustrated planning a whole trip around renting a car, because Hertz said it wouldn't be a problem... Only to find out we have to take a bus across Ireland, and not anything we wanted to.