If you mean parking it up over the winter months. You need to ensure good ventilation. Leave seat cushions propped up with cupboards open so low level vents are clear to ensure good air circulation all around caravan. Charge leisure battery up once a month. also its good to move wheels monthly. Jack up, spin wheel & leave it in different position about once a month is what I do.
No need for heating or any sort of moisture traps. Cold air is not damp air provided it can circulate in & out of caravan freely.
If wet is leaking through awning rail into inside then that needs reparing. It is a separate issue from how to store the caravan over winter.my previous post assumes caravan is in good condition with no exterior seam failure. If you are getting water ingress into structure of caravan then that needs reparing or caravan will be scrap in a couple of yrs.
Leaking on the outside of caravan but inside awning. I've sealed the top of the rail with multi purpose silicone. Didn't do much. I think it's coming in from where the awning meets the rail. Water getting in and under the track. Never thought about spinning wheels. Will give that a go. Do you leave blinds up or halfway or anything like that. Heard it makes a difference.
Leave blinds up so they are not stressed. If water is running between awning rail & awning then a drop of sealant on any joins in the rail might help. It's also a good idea to clean inside of rail recess with rag & meths to get the crud out then spray in some silicone lubricant or furniture polish to help awning slide in nice & should help stop water running around & down outside. My experience anyway.
My caravan wheels get rotated once, sometimes twice a month, it also gets plenty of air circulation throughout winter. Why winter it? use it throughout the winter months, nothing better than getting up on a nice fresh frosty morning. When it gets back to storage, just drain the water system and leave the taps open, until next time out.
The other thing about winter preparation, is how fast you can pack up the caravan and move, when you get a knock on the door just when the tea is cooking in the oven and table all set and you have to get to higher ground!!!!!!!!!!!