Look for original breeding sites of house flies

MGK

While many pest problems arise on-site, house flies and several other fly species can fly long distances; their original breeding sites can go unnoticed if you only inspect the on-site area. A livestock facility, dumpster, dog park, junkyard or other breeding source could be nearby, but hidden from view with only a line-of-sight inspection.

Sandra Sleezer, BCE

Google Maps can be a huge help in finding nearby potential sources. Communicating this extra information to customers can go a long way in setting expectations and helping them accept the potential limitations of what you can provide in a service. It also can raise their confidence in your ability and knowledge to handle their situation in the best way possible, by going above and beyond the on-site inspection.