Shocking service beyond belief.

The worst service imaginable. Bought a car 2 hours later it was in a turbo specialist for repairs. The turbo was about to fail it had a high pitched whine. Garage tells me because they gave me a discount I have no recourse. Its my problem - 2 hours after buying the car. They told me the vehicle is prefect they even have a Dekra check for it. When I asked for that report was told I can't have it. The turbo on the car must be going in the few kms from when I left the garage. Its unbelievable that a garage takes no responsibilty. I had to find me own way home 50kms they would not even apologize and I am a pensioner. What are my options?