Re: camp mold
When I used to close camp up tight I always had a strong musty/mildew odor when reopening. One year, we got mold. We just scrubbed the heck out of everything, used diluted Clorox to kill it.
Ever since, I let some windows partially open. One in the front room that is under the porch roof. It gets left open about six inches ad is blocked from opening further. One over the kitchen sink and a small window in the bathroom.
The cross-ventilation from doing that has made a huge difference. No mold issues and instead of the musty, closed up smell, camp actually smells fresh and aired out even after long periods of no occupancy.