Purchase advice Alfa 156 Gasoline

Hello, among other things, I take the Alfa 156 into the short choice, if I get a new car in the summer. Which engine can you recommend me? The 1.6 with 120 hp is a little too weak for me. The 1.8 with 144 hp or the 2.0 with 155 hp would rather agree with me. My budget is up to a maximum of 6,000 euros. And it should no longer have like 100 TKM on the clock. As far as the equipment is concerned, I have no high demands. Only el. FH he should have, since I almost every day go to the parking garage I drive about 25 TKM a year and therefore the car should hold at least 3 years/75 TKM. What is the workshop intervals for inspections/oil changes and the timing belt change? How high are the prices in the Alfa workshops? Bzw. what cost wear parts? e.g. timing belts, WaPu, brake pads, brake discs etc. At the moment I drive a Vectra-B. Can I assume that the Alfa is much more expensive in maintenance than a Vectra-B? Would I be very happy about a few answers Greetings Vecci16V