Sorry, maybe should have elaborated a bit more, we have a beach so no cupboard space, was thinking bedding, awning, gas bottle and other bulky items to perhaps leave the Cali more comfortable and spacious for travelling in.
The Beach takes a while to figure out where things go. Everyone is different, but it has more space than you probably realise. The more you get away and use it, the more you discover where things need to live etc.
We have bedding on top of the multi-flex, it all fits on there including toppers etc.
Clothes, sports goods, BBQ and miscellaneous box under the multi-flex.
Cutlery/plates etc in the first draw
Cereals in the second
Other foods in the third
Torches, wipes and various camping bits in the side compartment
Don't forget the door pockets and seat pockets
First aid and emergency stuff in the spare wheel jack cupboard at the rear
Levelling chocks with the chairs
Loads of space, pack wisely and it will all fit.
Think if you really need something, because most times you probably don't
This thread has a few ideas too
https://vwcaliforniaclub.com/threads/volkswagen-california-camping-with-babies.15687/