Too many \human errors"with my vehicle repairs"""

I have been sending my BMW X5 to this workshop for over 18 months and used to get superb service but NOT lately. Handbrake was replaced but the console cover was not refitted properly. I overlooked this and had it fixed when I sent the X5 for a valet service. I asked for the brakes / wheels to be checked as there is a scraping sound when I brake. I paid for the labour cost to have this investigated and was told nothing is wrong however the brakes still scrape / shudder when applied. Yesterday I collected my other vehicle, Opel Corsa, after a service and CV joint replacement. Upon almost getting home last night the gears disengaged and I had to leave the vehicle on the street last night. Today I asked for the vehicle to be fetched, sorted out and delivered back to me as I had just spent R7k on it. Shortly after the vehicle was taken away I was called to fetch it and was told that the problem had been that the CV joint hadn't been fitted correctly. I asked for my car to be returned to me as I do not have transport. They refuse to deliver it back to me stating I should be thankful that I wasn't charged for it to be towed back there today! They are not responsible for their mistakes.