For outdoor areas, I hang fake wasp nests ($10 online). Wasps are territorial and will avoid areas they think are already claimed. Works better than zappers!
In commercial spaces, we use specialized wasp traps with heptyl butyrate attractant. Catches hundreds without zapping - important near food prep areas.
After testing 5 methods, I found soapy water in a spray bottle most effective against individual wasps. Instant knockdown without expensive equipment or collateral damage.