Sven, They were built pretty standard, for the rental market. Normally they'd have a front bench with a fold up bunk/backrest. Some have rock guards over fixed pane front window, some don't.
The kitchen was a cooktop and sink, with icebox below the cooktop. A stainless hood went over the cooktop. The
furnace would be in the closet next to the door and above that would be the closet. The back dinette is 'U' shape with a table that drops down to provide the base for the bed. The 3
windows in this area should be sliders. Cooling was via a 'swamp cooler' on the roof. Essentially this is an evaporative cooler, not very useful in humid climates. Many people replace them with crank up vents or powered vent fans.
Electrical would be 12v and 110, with a combo 110
electrical plug and 15 amp gfi circuit breaker at one side of the upper kitchen cupboard. Mine has a 12V fluorescent over the closet, and before I removed it, there was a 110 fluorescent under the kitchen cabinet over the sink.
Torsion
axle was standard with sealed bearings, and a 'proprietary' set up for the hub and rims (which prevented theft of the tires while being rented.). So you are limited to using the UH rims with the hubs, or else replace with a new
axle which gives you the freedom to use other rims.
Welcome to the group, and good luck on the purchase. We'd love to see photos also

we just love pictures of Eggs!