On various camper modification pages there are questions about parts, pieces, replacements, and set ups. I have gathered these various examples to illustrate to other "newbies" who may be trying to figure out how that attaches or where to find something similar.
The front hitch area. In some models there is additional space here and some have modified theirs to add a touch of additional space by using the same type of metal siding seen here to form a "floor" and then welding "sides. Some have even taken truck storage carriers and adapted them to their space. As with anything, be weight conscious about changes and additions.
Some units come equipped with air conditioning and others are added later.
battery. These can be locked down. If yours does not have one, add to the propane tank a gauge so you can tell how much is in the tank.