I was slated to remove bees from a friends house last Friday. He has been fighting them for 5-6 years. I checked them a week before to get the lowdown and saw no problems. I show up Friday and there isn't a bee to be seen. I used a borescope in the wall and floor and couldn't even find dead bees or comb. Instead of drilling holes in drywall he opted to wait for a problem to develop or more bees to arrive. Apparently bees are like computer problems; I arrive and suddenly they don't exist any more.
I'll take more of these instead. $150 package for an hours work; almost as good as my consulting rate.