Carrentals.com - Bait and switch! Beware!
I just had the same bad experience on 2 rentals with National Car rental through carrentals. com for rental cars in Nice, France. I was charged nearly double what was quoted in my contracts on both rentals. Neither agency has refunded the overcharges or offered to do so although National has admitted their error. It's a "bait and switch" scam.
Don't rent through them!