Newbie???

Hi everyone. New to this and just getting ideas and working out designs etc

I am wondering if any vehicle to convert would have an interior space behind the driver area of about 6 metres long by about 2 metres wide. Must have full height for standing up comfortably . I want to zone areas for different functions ie sleeping pod, living area, kitchen / bathroom prefer minibus but van to convert would work also. I know it's a big ask but has anyone done a project that matched these measurements.

Please help a newbie to make some plans. Any help is greatly appreciated