VW Polo Demo

I bought a 2011 Demo VW Polo from Striydom park VW. Car had a noise since the day of purchase. Took the car back many times for them to replace bearings. I Replaced the Tyre's last year after I took the car back yet again. Still the noise was there. They worked on my cars gearbox and did I had to pay an amount of R8114.00 and replaced my tyre's on my own expense. After they fitted the car with like wise model the noise was gone. This happened last year June. I even contacted VW SA with no joy. Do I still have a case to claim the money back. My car still has the noise??? The problem is not with the tyre's or bearings, obviously the rims which could have been replaced since first complaint.