Useless!!

Took my car to them got quoted over R20000 to fix certain things on the car which they found was wrong on the car. 1 of the things was rear drum skimming. Note that before my car went in for the repairs my handbrake was 100% fine. Got my car back noticed that my handbrake doesn't work! Took it back to them so they said it must be the rear brake shoes which was not the case then they said my handbrake cable was faulty...so I bought a brand new handbrake cable from Ford. They installed the new handbrake cable and the car still rolling back with the handbrake up. They then say they might of skimmed the rear drums too much. Took the car back now it's been 3 days and still no progress jus excuses! I want answers and want my car back ASAP and fixed!!!