Ripped of by Dollar Thrifty

I rented a car from the East London Airport from the 27th of March to the 2nd of April 2018. When they were inspecting the car I noted that it was scratched all over and I raised this with the Inspector. He assured me that the code for scratches was 3 and showed me that he has put 3s all over the inspection sheet. To show him every scratch in the car would have been futile because the car was littered with scratches, no number of 3s could gave done justice to the number of scratches in that car. On returning the car, they are now refusing to refund my deposit citing that the car has scratches. I think they should fix that car first before renting it out if they plan on ripping people off on existing scratches. I am quite disappointed because I was not happy when I took that car now my fears have been confirmed because poor as I am I have just unwillingly donated R3000 to a huge company.