The tactic I've been using is to leave the back door open, then go upstairs and watch the door from a window, so I will know when she has come inside. If she sees me, she won't come in.
Taylor is onto my plan, and is abusing my hospitality to bring things in the house. This morning I watched in horror as he dragged in a large, filthy ham bone, which he keeps buried in the yard. I was powerless to stop him, because if I went downstairs, or yelled at him, I would scare my foster dog. So I cursed him in silence.