Good morning it was a pleasure speaking with you today. I inspected the interior of the apartment and the windows in the kitchen were partially open and unlocked. The wasps could have been coming through there, Or other window tracks. I treated the window tracks, cracks and crevices on the interior during my inspection on the exterior. I found a opening that squirrels are going into on the soffit on the driveway side. See image attached to your account. The squirrel is living in the back part of the home, but entering through the side of the wasps may be getting through there as well. I treated the exterior around all of the windows, doors, and soffits. Wasps still may be able to get in but they will die shortly after. Repairing the soffit, and keeping the windows closed and locked will keep wasps and other insects out. The tops of the windows were slightly down and insects could get through these areas. I did not find any nesting today. Please allow 10 days to see the best results. T