To repeat what you already heard.
MOISTURE WILL KILL YOUR TRAILER... If you don't take care.
We use the cottage in Winter. When we start packing up to go home we leave the door open to let out as much moisture as possible before we go. If you can leave a window cracked open, do it. Cold dry outside air will suck the moisture out.
Open all closet and cupboard doors. Parts of the trailer that stay cool will condensate the air and form puddles.
On the reverse side. If you want to heat the place up real quick, heat up some water for coffee or tea. Moist air warms up quicker than cold dry air. Don't boil up a large pot of water for pasta etc.