Something i never understand is why people put an enclosed trailer inside? My friends do it too... never understood it. I would just throw a tarp on it run a charger to the inside (if needed) and be done.
as for sled decks. When you go out west and you see some of these parking lots/passes that are 1.5 lane dirt roads yeah a sled deck might be nice. Going to a tight parking lot example rabbit ears on a saturday morning after a fresh snowfall you'll wish you had a sled deck because finding a spot with a 4+ place enclosed trailer after 9am is impossible and once your in that lot your stuck trying to get out.
Since you really dont have that problem around here if it were me... id go enclosed like everyone else said.
close buddy of mine had one - sold it after a year saying it was pain to climb up there everytime and if your going somewhere in a nasty cross wind it can get pretty shotty quickly. He had his on a 2500HD.
main reason I know guys that park trailers indoors, is so you don;'t end up with all the snow on top, or ice
which legally NEEDS to be removed before you travel with trailers(recently a lady got killed here when a chunk of ice came off a trailer, local media and police went nuts ticketing folks that didn't afterwards)
so that os a reason many like to keep a trailer indoors
NEXT will be for many that store sleds in the trailers
being in doors, you do NOT get as many temp swings or as much moisture trapped in the trailer with your sleds
which by the way is a main reason you really shouldn't be storing sleds in a trailer, they just don't breath enough, lots of moisture gets trapped in them,a s well as just heat!
so being in doors, is easier on trailers too, no sun on tires,way less moisture or as much to rot anything, from bearings /brakes to to??
lots of pluses if you have the space to keep a trailer indoors , to be honest! just like any other vehicle, out of the elements is a good idea!