is gone? Wow.
Think about what you want to do, and then think about how to do it.
You're gonna want tank gauges plus interior and exterior lights. You'll need to run exhaust fans in the kitchen and bathroom (if so equipped) and maybe overhead vent fans. You'll want a radio, maybe a TV, 12V
outlets, USB charging ports, and maybe a DVD player or whatever. Leave yourself a place to connect an inverter, too.
There's also a 120 volt to 12 volt converter slash battery charger
that you'll need, along with battery cables and connections.
The best wiring components are built for marine duty; you're gonna want fuses for everything (so a fuse block). Blue Sea
makes some good stuff.
Switches, wiring terminals, crimpers, heat shrink tubing, and of course - wire.
And when you're running wires, run extras. You'll think of something to do with them sooner or later.