It is best to remove the bees as soon as they move in, because the longer they are in the walls, the more bees will need to be removed.
Bait out in an Oak Tree
I love having bait boxes around the property
The Carp Bee Club had a nice 1 page article in the Coastal View
Link to the article below
Rachel and I were part of the Vanishing of the Bees screening and Beekeeper answer section.