With all the random steel I had acquired around the apartment complex (crazy how many bedframes people just throw away), I built a metal storage rack on the back door for my extra water jug and gas can. Without a welder, I improvised and glued/ pounded wood 6-8" into the cavities, which I then screwed into with construction screws. The storage rack turned out pretty great, and will save me space inside!
To pin it to the sheet metal of the door, I used some 12" long drawer track as a washer between bolts to distribute the weight across a greater area and reduce the chance of it pulling out.
I then used silicone on all the holes to waterproof it.
Someone was also throwing away an old ladder for a bunk bed, so I bent it to conform to the curvature of the van. I then used some miscellaneous metal I had pulled from bed frames to create a rigid cantilever to connect to the top of the van, and also an extension at the base with rubber boots from an old set of crutches I found (not pictured). This quickly sets against the side of the van and allows me to climb up and access the roof storage, which wasn't possible before.
Looping the webbing around the handle as a lock is very strong, so before you say "someone could break in", anyone could also smash my window at any moment, so this will do just fine! haha