48Rob and Arne both make good points.
Condensation of humidity is a problem if you have fluctuating temperatures where you TD surfaces will be cool while the air in and around is warm and moist. Heating the air could make things better, or worse.
If you are really going to lose sleep, then one of those "car bubbles" would be the best thing you can do. High-dollar car collectors use them to protect their valuable cars.
http://www.autosportcatalog.com/index.c ... 2/sc/15049
But, I think that's a bit extreme.
Like Arne says, if you keep the thing closed with a desiccant inside, and you keep the desiccant fresh, you'll be fine.
The main thing is to check on your TD on a regular basis, so if you see a problem developing, you can deal with it quickly, before it becomes a big problem.
And, most of all, keep the TD clean. That makes a huge difference.
I have owned four boats, and they were all too big for my garages. They all survived the winter because I kept them clean and aired them out when the weather allowed. It took some effort, but my spring cleanup was easy, compared to what my friends with boats went through after neglecting their boats all winter.
My theory is that you can either do a few minutes of work every few weeks, or you can wait six months and spend a whole weekend working to fix what got neglected. I chose the few minutes of work every few weeks.
CD