Car Rental in Ireland/CDW info

We ended up just purchasing it as the counter. It seemed to be the easiest and cheapest way to do it when we were researching

The Dan Dooley site shows CDW as included. On the example I did, it wants an extra 16 euro for "additional insurance cover" (compact car, 7 days, Dublin Airport). Confirm this is zero deductible?? Have read good things about Dooley, though we used Budget with zero deduct bought at counter, and it saved us when we were sideswiped by hit and run driver.

Purchasing car rental insurance is a bit different than compared to most other European countries. I too found it easier to talk with the agent at the counter once I arrived and they sorted out all the different options to choose from. No need to figure it out ahead of time!

Can we assume that the extra insurance will be around $20 a day or less, no matter who we rent from? (So I can shop and book ahead to find a good rate, even if I have to add extra insurance at the counter?)

"Can we assume that the extra insurance will be around $20 a day or less, no matter who we rent from?"
Probably not. Trying to sort out the matter of car insurance in Ireland can be confusing and frustrating, since most companies require you to drill down into the fine print to determine exactly what coverage is available and the associated costs involved. Getting an apples-to-apples comparison between companies can be extremely difficult, which is why many on this forum prefer to book with Dan Dooley https://www.dandooley.com/ since his seems to be about the only company that shows the total cost of the rental, including the insurance cover, right up front.
There have been many previous forum discussions on the topic of Car Insurance in Ireland - suggest using the search feature at the top of the page to read thru a few of them.
Personally, I like to have this sorted out before departing on our trips. The last thing I want is to be at the mercy of an agent while standing at the rental car desk on the morning of arrival.

One other thing: I rented a car from Hertz at Dublin airport & my self-drive package from AAA Travel included the super CDW. However, when I went to the Hertz counter, the representative informed me that super CDW did not include "tires, windows & mirrors." As this was my first time driving (& first trip) in Ireland, he highly suggested purchasing additional coverage to include this (no deductible). It was 4 euros per day & I had the car for 6 days. I did & don't you know, on my very first day, in Cashel, I hit a curb that was jutting out on the left side & blew out the tire. The cost of a new tire was 100 euros plus a 50 euros service call. When I got back to Dublin, there was no hassle from Hertz (except they only covered the tire & not the service call) & I was reimbursed on the spot for the tire. Moral: check your insurance coverage to see if these items are covered (most plans do not) & the gentleman at the airport said tourists were more likely to bust a mirror or get a rock into a windshield than have an actual accident. Buy this extra coverage.

We rented last October, and have reserved this September, from Conns rental cars, used to be called something like easy tour Ireland. Conn works through hertz. You can call him here in the US and he will explain everything to you, very nice man. All his quotes include all coverage including super. The only additional insurance you can get, if wanted, if for tire and glass. This way, everything is spelled out before you get to Dublin airport, after flying all night, and you are confused about which way is up! Such peace of mind! Then at the end, you just drop off the car, no hassles. It is not cheap but no worries about holds on your credit card, etc. The only to go, IMHO!