Abacoa and the newer builds off Central Boulevard are tightly sealed. Good for the electric bill, unforgiving when something leaks, because the moisture cannot get out of the envelope on its own.
Out in Jupiter Farms the houses sit on larger lots with a shallow water table and often older HVAC. Crawl spaces, garages and utility rooms are where we usually find growth on those properties.
Close to the water, salt and constant humidity are hard on AC coils. A coil that is not dehumidifying properly keeps the indoor relative humidity high enough to support growth without any leak at all.