30,000 km/year–> which machine according to experience with least maintenance costs

Hello municipality, hello car connoisseur, I am just about to have to buy a new car–> best annual car. I drive about 30,000km/year, of which are easy 98% for work path and small rest = private. Already with employer everything calculated (leasing, company car etc.)= everything too expensive, but boss would pay me a fuel charge. For me it means now, which car I get me. Had for 8 years an Opel Omega Kombi 2.4 with gas system–> was top in fuel costs, but only problems me repairs!!! What do you think of a Volvo Diesel? My not too big demands: everything from middle class (golf, astra etc.), diesel or gas, as an annual car max. 50,000km on the speedometer, 5-door MfG Kenny