Family car for 5,000km/year

Hello I need a new family car for 2 holidays a year and a few WE trips to my parents (~80km per direction). 90% country road / highway. So far I have tortured my Citroen Saxo with it. For 3 people + luggage was actually already too small but I could not separate from it. Now the second child is on the road and it is time for something bigger. A third child will probably not be there. Important to me is a as large a trunk as possible and small With my Citroen Saxo the exhaust is rusted every 2 years. Even if it has disassembled the KAT, this was not a big act thanks to cheap spare parts. However, the fuel consumption, engine power, design, volume, equipment etc. is not important. In the narrow selection Citroen Berlingo are depending on the model with the 650 L trunk and Fiat Doblo with 750 L trunk. In addition, there are also Peugeot partners, Renault Kangoo, Citroen C4 Picasso, Scoda Octavia. What I can’t judge are the repair costs or the reliability. I hope you can give me some tips or even advise against certain models.