Bad service at Mercedes Benz Constantia Kloof Rood

My name is Sibongile Mthembu, I have a serious concern Mercedes Benz Contantia Kloof Roodepoort, Gauteng with poor customer service and customer care<br> <br> My A 160 class Mercedes benz had hard a problem with starter, and then I took it to Mercedes Benz Constantia Kloof Roodepoort for fixing they made a quotation of R15 177.10 and I paid the deposit of R10 000, surprisingly when I called them to make follow up, I've been told that the car has another problem , they assuming that the problem is on the petrol pump which need to be replaced again, they did second quote, which went up to R24 583.30, Army (service advisor) and Vickie (Manager) promised to call me on Friday (30/10/15) to come and collect the car, which did not happened, after work I went to them to find out what the problem is, they told me that they now suspecting the censor that still need to be replaced because when they test drive the car it is doing the same problem it losing the power. The money went up to R32 797.50. Everyday problems are piling and they are the custodian of Mercedes benz. I went to them almost every week but now they keep promise to call me and never happened.