Tarp or cover for winter storage

While I don't use either I can tell you what I see at our storage facility. What I see, is of the people who use covers they are for the most part on the trailer or MH. They are not always cinched well and sometimes see billowing covers from the breeze/wind but they are for the most part covering the unit. Some are cinched nice and tight and appear to cause minimal abrasion, others not so tight and appear to move quite a bit but they are covering the unit. Tarps on the other hand I see many more flapping in the breeze, all on one side of the unit barely covering any of it, laying on the ground flapping in the breeze not covering anything except perhaps a tire where it has bunched up or blown up against a fence at the far end of the lot.
So while I don't use either I have certainly thought about it and have come to the conclusion that if I were to use one it would be a well fitting cover with plenty of cinch points

A few things I've learned in my 63 years of life. And I think I'm finally old enough to pass on my sage wisdom now.

1) Don't cut corners. Cutting corners will only cost more in the long run.
2) Get the right tool for the job. Trying to half-azzed fixing something with a tool intended for a different function causes nothing but frustration and skinned knuckles. Go out, buy or rent the right tool to do the job right.
3) Cost effective is not always "effective". Going cheap very seldom saves money.

In other words, now that I've given you my 63 years of life experiences in 3 easy steps: Get the right cover for the camper. Get one that's made for RV's, that's breathable, that ties all the way down snug, and made for the purpose intended. In the end, you'll be saving yourself a lot of frustration and expense trying to fix all the damage using something that was is half azzed.

Assuming the roof isn't leaking, I wouldn't worry about trapping moisture.

We have experienced abrasion in the past and stopped using covers. If they aren't really held down well, they will abrade.

Also, is the RV at your house? If not, every time a wind storm comes thru you will wonder if it's going to blow off.