Terrible Workmanship and Incompetence

I took my Corsa Utility for repairs at GM Westvaal Auto Mafikeng on Friday 6th February, I gave them a list of my possible faults, but none of them was attended to but instead I was charged R1500 for labour and Gasket Cover and Spark plugs, they said I can't take the car Friday because it was in pieces but still Monday nothing was picked up, on Tuesday they called me to pickup my car.I get there and I asked them if they checked my fuel tank since I complained bout it and since they took it apart but I was told I have pay extra thousand for them to check the tank , I opted Steven(Service Man) leave it because I could see the incompetence and to my suprise when I get to my vehicle the Hazard Button is off,air vent where not in position, aircon panel had marks from the ***** driver and when I asked the so called technician(Gift) he blamed the people that wash cars after repairs and he said he looked underneath the same panel to check the aircon but he don't know how it got broken, the whole day going up and down and the so called manager(Steven) avoiding me the whole day until I got help from a sales manager.*********** Steven doesn't want to take responsility for their mess,bad work.