Inspection of a 3-decker in Manchester, NH today.  Top 2 floors had serious bed bug infestations.  And got treated by the pest control company throughout this past month.  The first floor did not complain about bedbugs however the tenants are moving out, probably to avoid getting infested.  It turns out that the 2nd floor tenants moved out a few days ago.
Now the first floor tenants are concerned that the bed bugs are out to find them and feast on them, since there is no one left on the 2nd floor.
Bed bugs are notorious for seeking out victims in adjacent units and apartments if there is no one in their immediate vicinity to feed on.  They can travel up to 100 feet a day to find their human prey. In those old buildings, where cracks, crevices through the walls and ceilings and in the closets are common, bedbugs will use these easy routes to get to other units.
Both dogs did an intensive bed bug sniffing job throughout the apartment.  Verdict:  no alerts.  We followed with a thorough visual inspection of the beds and did not produce any evidence either.  Lucky for those first floor tenants!