I've had success using my nose and a cheap $15 moisture meter against walls and ceilings. In my case I was already pretty sure the moisture came from the roof when it rained so went looking right after rainstorms. This was after also running a dehumidifier in a formerly damp basement.
If a home has an active mold problem, it probably has an active water or moisture problem. What mold remediation people sometimes do as well is use an IR camera to try to find unusually cold (thus damp areas).
> If a home has an active mold problem, it probably has an active water or moisture problem.
Mold can't grow or spread without moisture, so a moisture problem is a necessary prerequisite for a mold problem.
So focusing on fixing any moisture problems is a great place to start. Feeling around walls and baseboards or climbing up into the attic in the hours and days after a big rainstorm is one way to get started without any equipment investment. Air circulation also helps dry things out, so make sure every space has some openings for air exchange.
I wonder if there's anything that can be done from an ecological perspective, encouraging the presence of (acceptable) organisms that consume the problematic fungal spore species.
Spores are kind of designed to not be valuable as food. Can you name some organisms that actually consume spores rather than eat and then poop them out?
It doesn't need to be the species' spore-stage per se, as long as it occurs somewhere in the lifecycle before bad-stuff-humans-care-about happens. Can we encourage any (microscopic) conditions that trigger germination that turns out badly for the fungus?
Kind of like how there are plant seeds we don't eat directly, but we trick them into opening up and eat the sprouts.
Infrared thermometer is also good to survey a room and look for cold spots which are associated with moisture (condensation and/or structural dampness increasing thermal transfer). A thermal camera even moreso (but more expensive).
I've seen situations where experts put different colored water soluble dye on different spots outside the house, so that when it leaks through you can determine the source. Presumably that's within reach for an individual as well.
If a home has an active mold problem, it probably has an active water or moisture problem. What mold remediation people sometimes do as well is use an IR camera to try to find unusually cold (thus damp areas).