Bad car bought with false Dekra report, bought the car for nearly R70000 and now had to spent almost R40k to fix is bad very bad. Hope to solve something

Bought a B200 turbo from webuycars in Durban. Did the short test drive up and down the busy street and no problems. Dekra report shows only 3 defect such as the driver seat being torn a little, aircon malfunction and a oil leak. The oil leak is mentioned on most cars just to cover them self. Driving back from richardsbay. After about 45min on the road the car shows oil pressure problem stop the car, oil low, coolant level low. Car was fine after stopping for a while. Car did not overheat or any problems. After a few days the car started with its problems and my wife noticed the car looses power. Send the car to a mechanic. After checking all the sensors, a week later and R4000 later no solution. Car went to another mechanic and noticed it was the oil cooler, head gasket, cv joint problems and the rhs back door does not open. Now after R32000 the car is being fixed, cv joints still needs to be fixed for another R3500. False Dekra report.