Put him up at a hotel near the airport and don’t have him stay at your place.

Worrying about the guest finding grandma’s priceless jewelry or opening the display cabinet housing the signed Michael Jordan game ball from his last game is something to be concerned about. Secure/hide those items in a locked closet.

Worrying about your guest opening your refrigerator or kitchen cabinet while looking for a glass to get a drink of water is simply an unhealthy fear. Have them stay at a hotel.