If you want to pursue swarms, I suggest (1) calling the local 911 service, police, and fire departments. Maybe even hospitals and doc-in-a-box clinics, too.
(2) sending a confirmatory notice with contact info, such as a 3x5 card, that all emergency-type services can post in a convenient location.
It'll be prudent to include disclaimers about how you won't remove wasps and non-honeybee pests.