I would give 0 if this option was available.
I use booking website to get car from them with payment made upfront. Showed up for pic up and I was told that I need to pay another 150PLN to get the car or I can go somewhere else. No manager on site, no helpline, no willingness to help from staff.
Upon return I was charged for returning dirty car. I used cat twice go get from airport to hometown and back. I was only car user and driver.