Time for the first car (used)

Meal, it makes sense for me to buy a car; for a while after the driver’s license, the purchase of a suitable vehicle might not be a bad idea. However, there is a discrepancy: I got into “deer, prollige” cars (that is, those that look like a lot of money; Mercedes S and BMW 7 come to my mind), but can’t afford it, at least not as a new car. Sounds stupid, doesn’t it? Anyway: a financially viable used car (up to approx. 250€/month ) from the middle class is the (wide) frame of my search. I am so far in Toyota and Mercedes vehicles and find the latter incredibly comfortable, but I assume you have more expertise. I am still undecided whether automatic or switching, my other requirements are low: I drive weekdays to 50 km highway, on weekends either not at all or further away to friends in other federal states (but rather in summer). I don’t need space. Fuel saving would be good Help!