Took the full insurance plan for 2 weeks, was 300€ and about 100€-ish for the car. (400€ total, plus 110€ for me, cause i'm younger than 25...)
Seems expensive but i'd say ~30€ a day is acceptable. They get like 10'000€ a year that way but also have all the service costs so it's fair play...?
Had ordered a Seat Leon, instead Got a Skoda Kamiq and had a blast. Was able to also go offroad and through difficult terrain without worries about having to pay for tiny scratches.
(Deliberate damage would still be your fault apparently and logically)
Just don't do some weird 3rd party insurance thing (they don't fully cover, you're responsible for proof yourself that u didn't cause the dmg / scratches as others here described). It's fine to rent through them but don't pay the 60-100€ insurance and hope for full coverage. I cancelled mine and just bought nizacars plan instead to not have paid double.
The 100-150€ more are well worth a worry free holiday imo. You're still cheaper or at equal prices as europcar and other big rentals with similar car for the money. (I'm guessing here but did some rough comparisons online)
(I only found out the 3rd party people don't fully cover everything because initially i didn't have a credit card lul.)
With full plan i just gave them my keys and went to the airport.
Bye malaga, i miss the sun already.