My friend used to say of our office: "We don't have enough horizontal space!"
We inserted wire closet shelves, upside down, so a retaining lip was formed and Sterlite in the "Shoe box size" About $1.50 each.
TWELVE will fit. We tried with and without lids..and voted the lids out of the camper.
I'm looking for other places to install wire shelves, like over the cabover's side windows, or above the sink.
I might even make a 'shelf module' that will fit in the back seat of the truck, to be stuck in there when we travel.