Unhappy client

I visited the Midstream branch to buy a car and was directed to Michael to assist further who is the sales man. As someone who has never bought on auction before, I asked what the process was in term of one to buy and was told I need to register, pay R5000 and go buy. I did as I was instructed and I got a car. To my surprise when inspecting it, I noticed its actually not the same car I thought it was. Apparently they where 2 exact cars( Renault Sernic Maroon colour) on the floor but only 1 was auctioned today which I wasn't aware of. I was given an impression that all the cars marked Auction where being auctioned today which was not true. I was not given an option to test drive the car, I also noticed that the vin number on the windscreen wasn't clearly visible. Speaking to Michael to help me resolve the issue he told me he was not allowed and can't do anything to help and referred me to his manager Mark. He also told me that he cannot help me, it's either I take the car or loose my R5000 and told me that all this was on the terms and conditions which where not even given to me. What makes me sad the most is that I had mentioned before that I'm new in this and asked for assistance which I wasn't offered. I am not asking for a refund but just to exchange the current car to the one I initially wanted which is scheduled for the 17th Auction. I honestly feel that I was not even appreciated as a client and wasn't given the service I deserve cause all I got from the two staff members was a cold shoulder. They only care about sales(money coming in) and not servicing the client as expected.. :-( :-(