DO NOT HIRE CARS FROM BUDGET - RIP OFF

We visited knock airport and collected our hire car in the rain - inspected it as best we could it was fine and brand new. At the desk we were told our damage waiver insurance was a rip off and we should buy thiers or pay £1500 excess on a card. We had the insurance already from axa but they insisted on the excess charge so we paid it. On returning the car the man said we had scratched the back bumper which we knew we had nt as it had been parked on the hotel car park against a wall in the corner all weekend. The mark he was pointing to did infact come off on wiping and we have taken photos to prove there was no damage however the guy made us fill a form in before we could go on which i stated there was no accident/damage as far as we were aware. They are holding on to our £1500 deposit and can charge what they like. This is a pure sham and for all we knew the man could of damaged the car on inspection as he went out alone. We have been told they are paid bonus's on damage claims. This has put us off visiting again surely the airport cant allow this to continue as budget are a direct link from their site - i have read lots of bad reviews about them on returning but presumed they were reputable as it was a link from knock airport site - will be disputing any kind of credit card transaction they try to claim !!!