I read your post about killing them in the house. Brought back a childhood memory. I was about 5 or so when a little grass snake got into the back door into the kitchen. I watched my mother and oldest sister pushing each other off a chair while trying to get away from it. They finally hit it with a hammer. They hollered at me to get out of there but I just stood watching the silliness.<quoted text>I said "repellent". I already know how to kill them but would rather they stayed away so I wouldn't have to get up close and personal with them.
You have a crawlspace under the house? Nice warm space with bugs to eat, and/or mice. Set off some bug bombs. Throw those mothballs under there. Make sure you have flashing at the bottom of any siding you have. Screened vents. Keep the ground cleared for a couple of feet around the house. You might try glue traps tacked where they can get in. Keep a hoe handy in the house. Get a mongoose for a pet.
Marigolds are reputed to discourage snakes, and squash bugs.