I looked high and low for a cargo carrier to mount on the back of my 5th wheel to hold a 100lb generator. Most of the hitch types I didn't care for because of the side to side movement. I stumbled upon this one for eTrailer:
https://www.etrailer.com/RV-Cargo/etrailer/e99050.html and liked how it mounted to the bumper and could be folded up when not in use. It also didn't cost a arm and leg like the Lippert ones that I have seen
https://www.etrailer.com/RV-Cargo/Lippert/LC243621.html). Luckily a friend was also looking for something similar and purchased the aforementioned eTrailer one. He is not very handy and wanted my help installing. This gave me a chance to see it up close and me being pretty handy, I was able to copy the brackets and use a old hitch one as the platform. I also made it so it was supported by the receiver hitch.