As seen here(from this reddit thread)), a pickup with a camper shell (“topper”) can make a very serviceable dwelling.

If you don't want to build a bed, you can leverage built-in features of the pickup bed to build a platform.

Pickups have recesses in the truck bed sides to allow boards to be placed across the bed; this is to allow the truck owner to carry large flat items like sheet rock and plywood flat over the wheelwells. You can place your own plywood across these boards to make a raised platform with storage underneath. Tupperware containers designed to store under beds are particularly useful here.

One of the downsides of having a topper is you cannot reach over the bed to get stuff out. A grabber pole makes topper life much easier.

Attach a hook or L-brace¹⁾) to the end of a length of a PVC pipe or dowel. With practice you will be able to push and pull items all the way at the front of the bed.

The pole can rest on the inside ledge of the camper shell²⁾ when not in use.