01 Jul 2015 6:38 PM:
Can't speak for Centauro specifically, but all the hire companies I've used block between 900 and 1200 euros if I don't take their insurance. Never had a problem and it's always been released within a day or so of returning the car. Note, they don't actually take the funds, just 'reserve' them so they can take the money straight away if the car is returned damaged. It's normal practice all over the world.
Community thread:
Has anyone hired a car from centauro at airport using paper driving license issued prior to 1998
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