Private purchase – warranty

Good morning, maybe you can help me. I bought a Mazda MX 5 from a private salesman on 18.10.2016. At that time he was 10 years old and had 193,000 km down. Due to the age and the kilometers driven the seller sold the car as a hobbyist car. Last week the car had a breakdown. The starter and the ignition lock is broken. The repair would cost 1500 €. The car cost 2650 €. The repair is not worthwhile. I don’t know what that means. Now to my questions: – Does the defect from the starter and ignition lock apply as a hidden defect? – Does the seller have to stick for it, since there are not yet 6 months around? – Can I return the car to the private seller? – Does the clause with the hobby car protect it? – Is there a precise definition of the hobby car? I blackened my purchase contract once and put it in the attachment. Thank you Chrischi MX5