Store it locked down ...
Our trailer is stored in the garage with a 35lb canoe on top all winter. This is one of the reasons we bought this unit.
If you are in an older garage scenario .. this has to be done because of mice and other little critters. We have never had any problems ... and from what im reading our forum ... its probably the oldest unit here .. built in Oct 2010.
So ..not to confuse the issue further ... i would button it down for sure.
on a side note: When visiting an A-liner dealer before we bought our A-frame ... we found the Elite model unit with 6 inches of snow on the front bench seats .. it was up all winter ..... but that was early March ... but still ..no snow should have even thought of getting between the wall and the inside.
2008 Nissan Frontier 4x4
2011 Rockwood A122