Dealership selling their problem cars to people

Good day

I bought a car, VW Tiguan by Auto and Dynamic Voortrekker road Parrow and within the first month the car gave problems using oil and warning lights appearing in the dash board. Then we took back and reported it to them and they kept the car and gave us a Check Spark to use while they fix the problem. It happens on three occasions within three months, they just give us another car to use an give back the problem and it cause us inconvience. Then we made an appointment with the owner to make another plan because we no longer want the car that gave us problems. The only advise he could give was to for us to use our credit card or put in a Goodwill claim. We, husband and I then decided to get our legal advisors to assist us as well as SA Ombutsman and VW SA, with no luck. We were then forced to trade the car. Went to a few dealerships and they not interested and we haven't even started paying on the interest. Then we ended up at Hyundai, did a trade in and took a car that is so expensive and not in our budget. We now having the Hyundai for three years and would like to down scale and trade it for an affordable car. We thought we were out of this mess, then the VW problem car we bought by Auto and Dynamic's shortfall falls onto our current car. Is there any way that we can get out of this mess. It still stresses me.