WestVaal ******** ruined my car

I took in my car for a key reprogramming and now the garage is telling me that the computer box needs to be fixed i told him that I didn't have and he assured me it wouldn't be expensive and I reiterated that he should inform me before anything the electric mechanic from diesel electric in Welkom sent me a quote to the amount of R30000 and I told them I can't afford it again they hit me with a quotation amount of R4670 which I negotiated with the Diesel electric mechanic. The Westvaal people are telling me that they won't fix my car and they won't refund me.