Deficiencies in passenger cars

Hello, have bought used cars from a car locksmith privately, with the assurance, car is top, also the TÜV was made the day before. Now 4 weeks later a brake circuit falls out (line rusted through). So car into the workshop. Result in the workshop. Car is not traffic-proof. Brakes in front totally worn out (slides and blocks), brake hoses cracked, brake lines totally rusted. Horror. In my eyes a cheekiness of the car locksmith as a professional such a car To sell and even greater impudence of the TÜV examiner. One plays here with the health and life of people. Actually the TÜV examiner would have to be deprived of the craft, because the fact of a crime is given. Note to think: A child runs on the road and you have to make a full brake, the child has no chance. Greeting illonk