Yup... a sobering experience.
I'm in a townhome. Not long ago I was working at my desk from home on a Wednesday when one of the new double-pane sliding windows *sqeeeaked* in the living room as it slid in the tracks. I grabbed the Model 649 and moved quietly into a good position, waiting.
I checked out front and found that the landscaping gardners were preparing to spray pesticides along the front of the house. Both were wearing filter masks and gloves. They had simply pushed the window closed as a courtesy. Since then I've velcroed small bells to the tops of the sliding windows in the event I'm not at the front of the house next time.
BillCA in CA (Unfortunately)