You look in the basement

In the basement you find headless extension cords and boxes full of the possessions of former residents.

The gentle knocking of the washer and dryer mingle with the humm of the heating system and water pump...

But this basement is uncommonly dry for a house in the area; there is certainly not a trace of Sentient Mold here.

1. You give up the chase
2. You lie in wait
3. You look in the attic