I've had a cover on my MH the last two Winters and have not had a problem with it moving around or anything else. I have a ADCO cover which has straps on front, back and underneath to tighten it down and secures it very well.
I live in Council Bluffs Iowa across the river from Omaha NE :-{. We do get some pretty good winds here in the Winter some gust up to 45-50 MPH. Plus I live in a valley which welcomes the wind.
we have always kept our camper under a canopy from Shelterlogic we get about 3-4 years out of the canopy it is not expensive to replace the canopy you do not need to replace the frame It has stood up to some really high winds here in GA We have it anchored down and found if you put the legs in something like a bucket with sand etc the wind does not bother it it is on the side of our house facing west we do go out in the winter a knock the snow off of it not sure if it would hold a lot of snow or not but we usually get more ice than snow We had our camper for 15 years and when we sold it it looked like new keeping it under cover makes a huge difference!
I'll have to check that out, I'd love to have a car port for it but our shade trees won't allow room for it. This Shelterlogic canopy, is that something you put up and take down each year? or do you leave it up?
we only took it down when we replace the canopy we have replaced it 3 times in 15 years the new Sunseeker we are getting is 25 feet long our canopy is 12x26 so we will upgrade to the 12x30 canopy so it is completely covers the RV it is really nice to just drive it in we had to trim our trees as well and we had to extend the legs 2 1/2 feet to make it higher good luck on whatever you decide to do