Got Con by Autoworks milnerton

My car had a miss fire and i took it to Autoworks Milnerton. I booked the car in and was told that they will charge 1.5 hours labor to fault find. ( R1033.28 ) I agreed and they reported back my car need new spark plugs and they quoted me R 1700.44 for 6 spark plugs and R826.62 to fit it. At this point i wonder if this spark plugs is gold with diamonds at this price. I called the Car manufacture for a price for plugs and they quoted me R 947.70. I called Autoworks Milnerton to inform them of this and they gave me stories and this is the plugs they fit. I ask if i can then get the plugs for them to install as i was not happy with the over priced plugs they quoted. I had no car so i was faced to uber around for parts. I then called the head office at Autoworks and explain to them how unhappy i am with the situation. I got a call from Autoworks Milnerton they will go a collect the plugs at Car Manufacture. I got a call later the day my car is fixed. When i got to them i was told that the car still have a miss fire. At this point i was wondering so what did i pay for fault finding if they did not get to the fault. I had to pay R2721.50 for a repair that was not repaired and when i ask about this they all look at you as if you crazy. I was then told they need to replace my Pencil Coils R 10 476.34. So i paid R1033.28 for no fault finding and R2721.50 for nothing and i left with the car exactly like i brought it to them with miss fire ..... This place is a total waist of money i will not recommend people to go here they don't have the knowledge on how to fix cars. I took the car to dealer and they fix the car in 10 min and no charge the EGR valve was stuck just needed Q20 and off i went. Autoworks Milnerton is ****** stay away.