Master Cars (Derby) Ltd in Spondon, Derby

i am about to write a letter as i can find no email address. I bought an old car back in June for £900 and expected it to have things wrong but expected it to be roadworthy because i bought it from a garage. As soon as i got home, the door of the car that the gentleman had kindly opened for me, would not now open. I have to open it via the passenger door... I am certain the dealer was aware.
Two weeks later I had to have a complete new exhaust as the old one was rotten and fell off while I was driving. Fair enough, must have been an oversight...no credible business would fob off a customer so i paid £140 to fix it... then two weeks after that, I discovered the heater doesn't actually work... it had been re-filled i believe, just to ensure a sale. Since then i have discovered the TWO leaks in the rad will now cos another £140. The front tyre that was pumped to capacity on day of sale, needs re-filling weekly... I realised this after paying a garage to re-align the steering wheel. So thanks Guys. I hope my measly £900 bought you a nice meal or two... Once again i am left with absolutely no faith whatsoever in the possibility of finding a genuine car dealer.