most efficent way of locating empty homes?

[Lorin K.]

I am lucky my job allows me to drive all over the region serving customs. Some times, I divert off the main roads into housing areas to do quick scans for empty homes. This is hardly a efficient way to find empty houses. Is there a more efficient way to find empty homes? Perhaps USPS would provide list? Utility company that has disconnected the hydro meter? Would they be inclined to provide this information?