Unacceptable service from a reputable company of AVIS

I hired an Avis car at the East London airport through Rental cars for usage from the 8th-11th of September, On arrival my wife and I waited almost a hour to get our vehicle ,also given a car, not what we booked. The weather in East London on the 8th was almost gale force winds and the car given was dirty and full of dust. I inspected it as best I could but on my return on the 11th, I was told the car had a slight dent, which must have been there when the car was given to me but not noticeable. Even though I am allowed 200kms free a day, I only used the car to the hotel and back and probably did just over 100kms in 3 days. The car was undercover in a separate bay and could not be bumped by anyone. Avis is very quick to inspect cars thoroughly on return but do not do that when cars are given out. Its though they know about it and want to blame the person hiring the vehicle. Due a function we had to attend we were also late for this due to the vehicle not ready on time. We intend travelling often to east London as a family member is very ill there BUT I will definitely not hire a vehicle from AVIS again. Service is totally unacceptable and the waiting period as opposed to other car hire companies is very very long and very frustrating. I have sent an e-mail also to Avis customer care and to date I have not also received a response even though they acknowledged it. The AVIS-reference number was ********** 86