Rip off!!!!!°

Got charged for something they messed up. Had a sevice appointment for 02-01-2018. Took it in on the 18 Dec just to check why the back windsreen wiper was,nr working. They quoted me R12000 for a wire harness and shock mounting. Told them to put a claim in against my extended waranty so everything can get done when it goes for the sevice. After picking the car up i noticed the back number plate lights where not working and it was before i took it in. Called and spine to Zander, he told me to bring it in, which i did. They charged me R1500 for fixing somtjing they broke and the winscrren wiper was working all off a sudden. Which the said the wire harness would have to be replaced gor R12000. Reporting them to the ambudsman and informing Bivest Warranty about the so called witeharness claim they submitted.