No RV is going to fit in commercial parking garages above or below the first level since most all have 7 foot height limitations. However, the difference between a standard garage door you can use is 10 feet for a Class B and 12 foot for a Class C. If you rent off-site garage space you might find that to be a limiting factor. I cited my local self car wash already. When I needed some body repair done on my first B I was limited to what body shops could do the work. Not all could take an RV and none in my community had 12 foot garage doors. Going to the Sun Road in Glacier NP has a height and length issue. The length is less critical since their own in park tour coaches and buses are 24 feet (extended body Sprinters) but there is a cliff overhang going west that would surely clip off a corner of an RV over 10 feet. I still say if you don't think there is a marginal difference between a Class B and a small Class C go drive the Needles Highway from Mount Rushmore to Custer State Park and come back and tell us so. Yes, it has been done. But would you do it with a small Class C?