dont know about the cover but have been on my roof several times. just installed some vent covers and checked the caulking. i mainly just crawled around when i get up there because it just feels safer, (i dont care for heights)
I have a 2014 model of the 195bh and the specs on the website list "walkable roof".
I also got a cover but haven't taken it out of the package yet. I couldn't imagine how you would put it on without getting on the roof.
Got the cover on and it fits fairly well. Of course a cover that would fit 18'-20' travel trailers is gonna be a little large in certain places but it has plenty of adjustments to take up the loose areas. The quality looks excellent.
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2018 Coleman Light 1805RB
2010 Chevy Silverado 4x4
2013 Salem Cruise Lite 195BH (traded)
Ive got a very similar version of your tt and Im getting ready to put a cover on it for the first time. Hopefully I wont have to climb on the roof. Not crazy about that.
According to ADCO covers you measure from the rear bumper to the front of the tt but not the hitch or propane or battery.
We are in a seasonal cg and the owner winterizes for us at 1.75 per foot. I'm having him put the cover on this year but don't know yet how much he'll charge to do it.