Cabinets

You almost certainly do not want conventional-depth cabinets in your van (unless you have a large vehicle that's very wide), since they will take up a lot of your total living space permanently and make your van feel much smaller. If you are using pre-built residential cabinets, you may wish to cut some of the back off to make a shorter depth.

When purchasing or building cabinets for your vehicle, hardware durability matters. Latches, hinges, and struts are generally designed for use in a building, not a moving vehicle, so inexpensive hardware may fail sooner than expected.

Toekick drawers

In lower cabinets, consider adding toekick drawers for extra storage for small items you don't need very often, like papers or special tools. Toekick drawers, located at floor level under the cabinets, don't make sense for a sticks and bricks home, but in a vehicle the extra storage space is valuable! It also serves as a hidden compartment since most people won't think to look there.

Foam bones

Consider building foam bones cabinets and other structures in your vehicle. Reinforced XPS foam is lightweight and can be very sturdy. It may be cheaper than wood or other materials as well.

Reducing rattling

When driving, especially with off-road travel, things inside your cabinets can move around a lot.

You can add liners or cloth to the bottom of your drawers and cabinets to help. For pans or other large items, consider creating a custom foam insert with indentations for your items. This keeps them from sliding into each other and the sides of the drawer or cabinet. See this video. Put a tea towel or similar between lids, plates, layers of silverware or utensils, etc. Use rubber bands or other fasteners to wrap bundles of silverware, hold lids in place, and so on.