My 1999 Foretravel doesn't have slides but does use the airbag suspension for leveling. So when arriving I'll have to idle until I'm level. If I had slides like in my previous coach I'd have to leave it running to extend my slides while at ride height. Then level. After that I could turn off the engine. Same sequence when departing. Start engine, let air up to ride height (if slides then pull them in), then pull out. This does take a few minutes each time and is necessary.
As far as letting the engine and turbo, aftercooler, etc. cool down this is usually done just idling driving to my site. Not all motorhomes need the same sequence.