I have lived with wood-boring bees for 44 years and had several opportunities to watch them at work. Here (St. Louis, MO) they seem to have two kinds of projects. One is laying eggs and the other is creating and living in a nest/hive. I don't know if these are both solitary bee types, since I've never seen the inside of the nest.

The laying eggs project seems to be a one-time thing, as in they don't keep coming back to the same hole every year, they build a new one each time. They drill a perfectly round hole about a half inch in diameter into the underside of wood. I have a small balcony attached to my house, made of three or four 2 by 6s. I don't know if the original wood was treated or painted, but as they got older, the bees drilled out more and more holes. Before we replaced them, there was so much drilling going on, there were piles of sawdust below them. So the bee suspends itself in mid-air under the wood, and drills up. When the hole is deep enough that the bee can go in it, it turns and drills sideways. The eggs are laid in this tube. When the eggs start to hatch out, they evidently make noise. Woodpeckers hear this and come and peck out the wood to get to the eggs to eat them. It really wrecks the wood.

The other kind of project occurred above the balcony in the small strip of wood over the windows between the stone of the house walls and the vinyl-covered eaves. It looks like the same kind of hole, but after a while, stuff starts coming out of it. Maybe a mixture of waste and honey? It got very messy, with that stuff streaking down the windows, plus I didn't know what was happening to my attic, so I called a pest-control dude. He pumped alcohol into the holes with a pump sprayer. He claimed it wouldn't kill the bees, just stun them, and then they would fall out of the holes, sober up, and fly away. Then we filled the holes with a foam stuff that expands and hardens, so they wouldn't come back. And to keep them away, we covered that exposed wood strip with cut pieces of metal. It worked, but they moved to the porch eaves. I don't know where they went after I had the porch redone and covered the outside wood with metal/vinyl. There are plenty of trees around with dead branches, plus the house next door that is all wood siding and has been vacant for years.

Before the porch was redone, there were a lot of skinks living in the roof. One of them got into the house, and I couldn't catch him to let him out. He would come out of hiding to sit in the sun on the carpet every morning. I started putting down water for him, hoping he would find his way out before he died, but I don't think he did. He lasted at least a couple of months, but then I stopped seeing him, and later I found a dead skink behind the freezer.

And snakes. I've had black snakes in the house a couple of times. They are easier to chase out. The thing about black snakes is that they don't coexist with copperheads. So if you have black snakes you know you don't have copperheads. Therefore, you never kill black snakes.