I had to install a wood frame inside the trailer so as to be able to install insulation, plumbing, electrical, and insulation. My uncle, who has construction experience, had to do this part for the most part. First, we had to install the inverters and breaker boxes needed for the off grid solar and wind electricity setup. This is an overview of what we installed.
Closer view. From left: 1600w inverter for cooking appliances, 600w for AC/heater, AC breaker box, 450w for general use.
From left: Charge controller, 400w inverter for fridge/freezer, DC breaker box.
He had to glue small stubs of wood in the gap between the steel frame and the roof on the back wall as anchors for the roof studs.
He had to bolt the studs for the walls in horizontally due to the orientation of the steel frame.
The opposite wall. Note the framing around the wheel well.