We had lwb t5 conversion (now have a caravan so oodles of space to carry around tat) it had a narrower bed and then cupboards and kitchen stuff, hob and sink along the edge, one space was the fridge, in the cupboard under the sink we kept all the pots and pans, crockery, the kettle, lantern, bin bags, washing up stuff, the leisure battery was in there too.
The gas bottles and water carrier were next to the bed/seat accessed from the rear and there was a cupboard above that we stored clothes, games etc.
2 drawers/drawer sized cupbords for cutlery and food
Little wall lockers for mugs, tea bags, playing cards, batteries etc.
For a long time we had the bench seat at the front which had a large storage area under it, loo rolls, wash kit first aid kit, laundry stuff and pegs a fan heater.
Bedding went under the bed/ seat each day, that takes up a surprising amount of space.
So we definitely used the cupboards and you will fill any availability space BUT the bed was tiny, Dh and I are slim but it still felt small for us. In the end he slept in the pop up roof with one DC (bigger bed) and I shared the bed with the other DC.