worst service ever

I took my car in for a service in the morning and was told that the service would be R3800 . I was then called around 14:00 to be told my breaks must be replaced and skimmed this would cost R1700 and said it is fine to do then. At 17:00 no has notified me about my car yet and called them to find out what is happening was told the car is finished and I can come fetch it problem is they know I have no transport and was told all the drivers left a 16:00 already after a while they got someone to come pick me up and take me to GM. When I got there and need to pay the bill with the labor discount was over R7500 only to find out the service with discount price was about right but the brakes was close to 3700. This is disgusting service from GM and and if this is what you call service nowadays I will go buy another car . I am very unhappy that I supported GM my whole life and told people their cars and service is top quality as this has proven it is a lie.