Incorrectly billed for services

Supplier books in 30 cars on average each day, and has 5 mechanics to service these vehicles. VW charges R820 per hour.<br> I was charged 7,4 hours, of which 1,9 as per invoice is for the service, rest was specified/quoted. From when approval to progress with the specified/quoted items, there was only 4.3 hours left to when I received the SMS notice that my vehicle was ready for collection, yet I've been charged 5,5 hours. That equates to R656 overcharged. <br> I told them that I did not want the wiper blades replaced. They were not included in the final specific/quote of work to be performed. They were also not shown as an item that was listed in the parts used, yet I've been charged a further 0.3 hours for the removal and installation thereof. <br> When I challenged them on the hours and the rate, they indicated that they use apprentices (same rate app**** as qualified mechanics), which is the reason why they are able to charge 30 people each day for a full days work, when it is practically impossible to work more than a sixth of a day on your car at current volumes. <br> Their sick company culture of *********** the customer continues as per recent emission scandal cover up