Car worse than before Service

I am purely disgusted by the service and treatment i recieved from this company. Took my car for an early service because the ABS light came on the week i planned to drive from PMB to JHB. Was given a R6000 quotation for the service and changing of brakes which initially was told would fix the problem. I go fetch my car pay guess what, the ABS light is still on and not only that my car screeches horribly when i brake. They say the screeching is because of the new brakes and will go away but that i now have to buy another part for my car cost R750 and they will put it in \free of charge"to the ABS thing. I do that and on my return the ABS light still on and they say they have tried everything to fix"