I owned a prevost marathon conversion, so I can say first hand that over the life of the coach it will cost you about $3000.00 - $5000.00 per year, cost of ownership.
Not like a ford chassis motorhome.
Tires around $600.00 x 8
Batteries around $500.00 ea x 12
$600.00 oil changes
Air brake dryers, antifreeze, conditioners and filters.
And that is just normal wear and tear items.
Everything is big money parts like you would buy to fix a semi.
Miles of wire to go bad in places you dont want to know about.
The over the road bus A/C was a nightmare of leaks.
Forced hot water heat "wabasto" was nice to have.
No storage as it is all used by A/C systems, bus air as well as 3 house systems.
I think there was 6 air tanks and a jillion feet of somewhat leaking air hose that prevost says is normal.
Well, its not "normal" when it gets cold out and one side is up and the other is down.
Got rid of it and am still trying to decide what to buy next but unlee I win the lottery and have never ending wealth it will not be another bus.