Storage Pockets - These have velcro at the edges and are secured with adhesive velcro.
Small 'eye hooks' and a short bungie to hold the pass through open while passing items through galley.
Pure Sine wave inverter to run CPAP....Yes I snore! :) Also has 2 USB ports
Added LED bulbs.
AUX solar panel port.
Our 'grey water tank'. This was a 20 year old water container which just happens to sit under the trailer nicely while the canning funnel catches any grey water.
Added a small shelf under sink. 2 liter bottles x 4 can be stored underneath for 8 liters of water for washing etc. The top holds our extra fuel canisters. Shelf isn't pretty but it was a tight fit without removing door. Also wanted easy access to mechanicals.
Under trailer removable (for traveling) shoes or wet things storage. Aluminum channel attached underneath and tub lip slides out on them.