I'm pretty sure I know who they are. My wife and I got an estimate for windows by a company through Home Depot. Evidenty the guy who gave us the estimate left the company for some reason and they said they'd like to give us a "re-estimate". The first was $10,000 so I can't imagine it being even half that much.
They never leave messages; I work in a sales position that requires outbound calls. SometimesI leave messages and don't others but once I realized they don't have an interest (not returning my calls) I stop calling.