Welcome to our little corner of things...
Make sure that each system in the rig is checked-out and fully explained to you.
You've got Water, Sewer, Electric, Batteries, 110 power, generator, heating, cooling, stove, Refrigerator, Levelers, slides, tire pressures, chassis engine and transmission... and probably a whole bunch more that I've forgotten to mention!
The best of luck to you with it!