I've learned the hard way that tarping the trailer will retain moisture in the PNW. The past two winters have proven very moldy for my Boler
77. I'm up to 4 damp rid containers and 1 humidifier that I plug in every month to re-charge the crystals. Yes, 2 windows
are opened a crack for airflow at all times. Even in the summer, I refill and dump water out of the containers. I often wonder if dri-z-air would be better for the moisture. I don't have access to electricity when the trailer is parked, so there's no way to plug anything in, unless it was a 12 volt, then I wonder how quickly the battery
would drain. The good part is that the inside and outside are scrubbed squeaky clean each March. Some things are just a labor of love.