nikwax wrote:so is the real advantage of Romex in home building that it is cheaper and easier to handle than other methods? Nothing to do with safety?
Romex is required by code for house wiring. NEC
What ever you use to to wire your trailer make sure it has a ground wire. You can get outdoor rated portable cords, one is SJO rated which is rated at 300 volt and get 14-3. As a rule of thumb, it is 15amp rated and will be grounded. SO is rated at 600 volts and 14-3 and it will still be 15amp (as a rule of thumb). So anything that is 14-3 will work for 15 amp rated breakers depending on your distance run.
I used solid in my TD cause I had it. Made the strands longer and ran them beside the outlets instead of behind. Just took some push and shove.
You can also strip back the outer sheathing wires longer so you are only dealing with the single wire when bending. Leave extra in case you have to repair.
The best advantage Romex has is it is easier if you are using stab in fixtures.