Blatant ripoff, don't deal with these people

Since my regular and much trusted mechanic, who did a number of jobs for me in the past, was on holiday, I contacted you to repair the brake fluid leak on my 2006 Hyundai ATOS. Your men showed me that the pipe, connecting the brake fluid reservoir with thewheel brake was defective and was the reason for the fluid leak. I assumed that one of your men is going to immediately buy a new pipe and come back to install it. Instead, he came back very late in the afternoon and hastily installed the pipe. He quoted verbally R800 .He gave me your banking details, and I immediately transferred this amount to your account by Telephone Banking and gave him a printed copy of a Proof of Payment. Originally I also requested to give me a quote for repairing an assumed oil leak. He took a look, gave a very superficial quote of two hours of labour, said nothing about parts, and vaguely pointed at one end of the motor block saying that there was the oil leak. He never took the trouble of crawling under the car to get a better diagnosis. I subsequently received your invoices for the brake fluid job as well as for the assumed oil leak, where I found that the two hours of labour were jacked up higher and a mysterious part for R500 was charged. Seeing the superficiality of his diagnosis, I did not believe a word of it anddecided not to give you the go ahead with the oil leak job. Yesterday, a few days after your having repaired the brake fluid leak, the brake suddenly went limp again. My regular mechanic whom I trust, was back and he looked it. He showed me that the leak occurred at the end of the pipe at the brake fluid reservoir, EXACTLY at the same place where your men originally showed me the defect! Upon further examination the pipe, I am now convinced that your have never purchased a new pipe, but tried to fix the old one and installed it! Now I have to pay again for fixing the brake fluid leak, since I paid you R800 for nothing. I have now the invoice that my technician paid for the pipe. It is for R350. This is further proof that you simply reinstated the old defective pipe instead of buying a new one, and you still charged me R100 for it. What cheek! This was a shameful ripoff which I have never suspected from someonr like you.. YOU POCKETED R800 for nothing!