Add a clam shell style roof-top carrier. Clam shell carriers provide roof top storage space that is watertight and in some instances, locked down. Clam shell carriers are available at most camping supply stores. Provide your camper make, model and year to match the proper clamshell and rack for your rig.
Mount a steel grate bumper rack on the back of the camper. Steel grate racks provide a platform to attach bins, lock-boxes and sporting gear, giving added storage outside and inside the camper. You end up storing some items on the rack you would normally put inside, thus freeing up space inside. Like the clam shells, these racks are proprietary to your camper model. Provide the camping store your camper's make and model to match the right sized grate rack.
Remove extra tables or chairs from the camper. If your camper has a dining table and an extra recreational table, consider removing one of the tables. This provides extra space in the camper to place plastic storage bins, or to add dedicated camper shelves or cupboards. Most tables are removed with a wrench. Store the removed table in a cool and dry place for future use.
Install cupboards above sleeping quarters to add enclosed storage. One downside to this is decreased head space for sleeping. However, if this is not an issue, add cupboards above the beds and store soft goods such as extra clothing or linens.
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