Good questions!
Slides... Those full-wall slides do put more of a strain on things.
I don't know how the statistics look; but I avoid them, and woulda prefer two slides.
The refrigerator...
Mine is a 3-way unit, and it chooses it's own power source.
Air Conditioners...
They might not put a unit over top of the bedroom, in order to isolate the sleepers from the noise.