If and when Diamond ever finish their DA50, that might be interesting. It's designed for four fat Americans (or four fat Brits
) plus golf gear.
Otherwise, few singles apart from a C182 kind of thing will carry four big people, any distance.
Whichever way you go, if you want load hauling like that, you will pay a heavy price.
It seems to have been regarded as a marginal market for decades, and a big cockpit will directly hit the MPG even if it is flying empty.
My TB20 has a 500kg payload and will carry four "modern size" people and about 4hrs' fuel, which in practical terms (alternates etc) is almost halfway into France, from the UK s. coast. That's quite good actually. But it would be cramped if they were fatties
It also won't do 650m grass, at MTOW, ISA+something, etc. 800m of very good grass OK or 500m tarmac, but not 650m "average" grass.
A friend has a C182 with the canard kit (N-reg obviously) which is awesome on grass.
These forums get regular posts like this... somebody new to flying who is looking to transport their family. I might have been at that stage when I started flying. One has no idea which way the design compromises in GA have been positioned, and it is a bit of a shock to learn how much you have to pay to get that capability, with the ability to do e.g. foreign trips. And within the UK one can usually drive in less or similar time...