Find reliable car (7000-8000€)

Hello together and thank you for reading, after which my current Mazda 323f (type BJ) bugs me in almost every way that there is, I am looking for something newer (or better). I originally wanted to have something within a radius of 14,000€. Everything was clearly 318d or 320d touring (my dream car). Unfortunately soon there is also a separate apartment, so that the vehicle ultimately suffers from it. The following is important to me: – max. 90,000-100,000 km – preferably diesel – high quality / high quality – consumption – low maintenance / reliability (also insurance, since I am still U25) – min. 120 hp I drive about 13,000 km/a. Mainly federal road. Since there is not much in the budget up to 8,000 I have looked at a slightly older A4 Avant:http://www.tuningsuche.de/…/…-a4-avant-8e5-b6-06-2002-von-mk10.jpg Since there are not many other combinations in the price range alternative also the consideration between a Golf 5 or A3 where I am afraid of the insurance costs. How do you see that? Do you have other suggestions? (one is always a bit of a business lind) I am grateful for all the comments