A cell phone with CoachNet number on Speed Dial is the best emergency tool. If breakdown beside the highway, getting towed to safe spot is my first concern.
I have a 96 motorhome, so have the age concerns that comes with such a machine. My limited replacement parts box has: fuses, sepentine belt, radiator hoses, light bulbs, and some hunks of fusible wire. Ford 450 parts are easy to get via overnight service so not hard to find after you determine what is needed.
Tool box has Rescue Tape as my primary go-to product for everything from electrical to water leaks. The usual Eterna Bond, Duck Tape, Metal Tape, Super Glue, Silicone Spray and WD40 goes in any RV.
Battery jump pack and Air Compressor take up a lot of space but great when needed. To save space, the Schumacher model SJ1332 does both, and provides an inverter too for low-wattage use.
I do not leave home without a new spare tire and an unmounted old one for emergency backup. Some would not have all of the weight and space of a spare, so it is a personal choice.
