Yup, I recently rented a car with an American Express Platinum card, which includes secondary coverage. I don't own a car, so I don't have auto insurance, and assumed vehicle to the damage would still be covered, I just wouldn't have liability coverage. But in order for the policy to pay out anything at all, you're required to have primary coverage.

So I ended up paying $300 or so for a scratched fender. Not the end of the world, and their estimate seemed fair, but I might buy the rental car insurance next time.

> They also don't cover damage to other cars, only to the rental vehicle itself.

But that's covered under the liability insurance, which is mandatory in most jurisdictions and included with base rental fees already. In the US it's mandatory, too, AFAIK, but the the default insurance will usually cover the minimum required by the state, so you may want to have a separate liability insurance after all with a higher coverage.

The trick with Ireland is to buy a policy ahead of time that covers the EU. If you neglect to do this, you will need to buy the overpriced policy at the counter.

Many Irish roads, even near very popular cities and attractions, are extremely difficult to navigate in an automobile. Very very narrow with virtually no shoulder. Accident rates, especially among renters, must be very frequent.

https://images.app.goo.gl/arKbAkKnWK1Qqi3o9

This example is far from the most difficult, it actually has a center stripe and shoulder markings. Many similar roads are tighter with no markings, and also with blind hills and curves.

If I was an insurance provider, I'd certainly try to exclude Ireland.

Insurance costs in Ireland are much higher than the UK.

You also want to be sure they cover loss of use, which for a rental car would be the max daily rate for every day the damaged car is out of service for repair work.