I use Bifen I/T to spray the foundation around the house as well as the porch and the door. I also spot spray any wasp nests etc. I encounter. Works amazing and lasts about a month during summer. Doesn't stain anything I spray it on as well.
I use a 3M spray painting mask when spraying.
Two of my neighbors were paying a "pro" (about $30/month each) to come and spray their houses about once a month and they still had insects in their house. One of them had a wasp nest around their garage door about a week after the guy supposedly sprayed the house. I came over with Bifen, sprayed the nest and no more wasps. Needless to say, they cancelled the service, bought Bifen and are DIYing the spraying themselves.