We will "build it in". so to speak and see if we can handle a Montana winter.
I have a family friend with a mobile home parked on Mt Hood, in Oregon.
While awaiting a windfall (that ain't ever gonna happen) and being too proud to sell her land and move somewhere safe, and having no money to repair the roof... the roof has absorbed snow melt over the years and bowed downwards to where you cannot walk upright in the mobile home anymore except along the edges where the walls are.
There is SEVERE mold contamination.
I consider it a 3rd world hovel. It's bad.
I've offered to go up there and install a semi-permanent railed canopy over the top of the motor home to keep most of the winter snow-weight off of it... at my expense. As well as to repair the roof to the best of my ability.
My parents have offered to allow this person to simply leave the property, and live with them in perpetuity.
Both offers have been rejected so far.
Beware snow, on flat-topped structures that are not intended to bear the weight of snow. Granted, Mt Hood suffers from "Cascade Concrete" that you probably don't get up in Montana... but that 5th wheel probably has a weaker roof than a mobile home.
If it's gonna be semi-permanent, it would greatly benefit from a railed canopy being built over the top of it, with strong tarps to keep most of the snow-weight and freeze/melt/freeze/melt cycles off your roof.