VW ripping us off on parts and service

VW SA is thumb sucking prices when it comes to service, I was given a written quote of R5800 and some change for cam belt change on the polo 1.2 tsi 2015 model, on the day the price escalated to R7800 and some change, when I refused the service it dropped down to about R6300 and a some change, after the cam belt change, about a week later the car started making a noise under the hood so I took it back in and upon inspection the service technician diagnosed the car and pointing the AC compressor as the source of the noise,I was asked to book the car in for repairs to be done but instead of going straight to the source of the noise they told me the technician will diagnose the car R1300 and thereafter order the replacement part, the Aircon Compressor, when they finally called back I was quoted R23000 and some change for the Aircon compressor and was told that’s the best they can do,I have warranty and was able to only get R10000 and an additional R4000 after some negotiation but VW will not budge and the tricky part is that I will forfeit the R14000 from my warranty should I take the car elsewhere since the warranty insurer has already granted VW authorization,Covid 19 has not made my money situation easy and VW is only compounding the burden on my shoulders,in that the authorization is only valid for about thirty days from the date it was issued, if at the end of the month I don’t have the extra R9000 my car will not be able to cool down and I’ll continue driving a car that sounds like a tractor due to the noise coming from the AC compressor,really disappointed in VW I thought highly of them but the wool has been pulled from my eyes.