Reason decision, family with 2 children

Hello all, would have a small request for interesting suggestions about my situation: Have a Ford Galaxy (Bj.2000) which I now have to sell and for which I would get approx. 1500€. I can find 800€ to 10,000€. I now want to buy a car, rather a station wagon or limousine. Drive in the year approx. 15 to 20 tsd. km. Think that a diesel should produce least cost/km. Safety and reliability are important topics. Trust only with a previous owner and checkbook care (Room Bodensee) What would be the most reasonable thing? 1.) A Peugot 308SW Built in 2008, a few kilometers, 2.) A Ford Mondeo, a bit older, with more kilometers 3.) Opel Vectra , a bit older, with more kilometers 4.) Or put aside an even cheaper car and money for the repairs. 5.) What else. Car brand/model would meet the above criteria ? Would I be pleased with answers. Greeting webcruiser