One problem in my opinion is that there is no really simple answer to a very broad and vague question such as "Am I covered by third party liability insurance for any risk when driving my rental car on the island when I have refused to purchase the "optional" liability and the rental car company is implying that without purchasing it, I do not have any third party liability insurance covering me when driving my rental car?"

Dutch and French law requires that a rental car have third party liability insurance - the rental car companies MUST have it on their cars, even if the "optional" insurance is not purchased by the renter of the car. Now, does that eliminate any questions? Not for me. I am uncertain about whether there can be exclusions from the required coverage, questions about deductibles, and questions about whether rental car company (or its insurer) can shift liability from insurance on car to driver with contractual language or the facts of a particular situation. The obvious starting point is a careful review of the contract you sign with the rental car company.

If I really cared enough or was curious enough, I probably would engage an island attorney to get me a precise answer to the questions I might have - but I do not care enough to pay for it and neither do I care enough to ask to get an answer for free.

As a practical matter, I do not think it necessary to purchase the optional third party liability insurance, but my wife, whose picture is in the dictionary next to "risk-averse," often likes to buy it even knowing that it may simply be a gift to our favorite rental car guy.

With regard to CDW, just get a credit card that covers the CDW for renting a car on the island. Many of the cards I have had, even some supposedly good cards, have stopped providing it. As of now, I have a IHG card that still provides it, but I will check again before next trip.
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