I'm in the process of moving out of one RV trailer and into another. Today I noticed a couple of other things we haul around.
1] toilet wand. It helps flush the black water tank.
RV Flexible Swivel Stik - Camco RV 40074 - Drain & Flush Systems - Camping World
1a] Johnny Chock. Holds the toilet valve open while you use the toilet wand.
Johnny Chock - Prime Products 17-0115 - Drain & Flush Systems - Camping World
2] electric plug converters,
30-amp male to 15-amp female, and
15-amp male to 30-amp female, and
30-amp male twist lock to 15-amp female, required to plug the trailer into my Honda 5000 generator, and
Short cord with 50-amp male on one end and 30-amp RV female on the other end. That last one is used only if the campground you stopped at the last minute before dark in 110° F. weather has only 50-amp campsites available. No problem. I can plug my 30-amp RV cord into that 50-amp source using that foot-long converter, then my AC works great. Whew!
Don't let Sweetheart forget her dust pan, broom, and whist broom.
Flashlight(s) and extra batteries.
Extra fuses of all sizes for both the 12-volt and 110-volt fuse box/converter/inverter.
Two or three-step step stool if anyone is shorter than 6'.
Also you'll see lots of folks with 8' step ladder or extension latter strapped onto the back of the trailer.
Extra light bulbs for tail lights, parking lights, and lights inside the trailer.