Maybe a plastic sheet under the sheets to protect the bed from bodily fluids? Something like we used to use for our young bedwetters. There was once a slight problem with someone who was a squirter wetting a bed.
Some small paper bags marked with used condoms may help in not finding used condoms thrown under a bed later? It happens.
Leather furniture instead of cloth. Towels readily available if you are worried about furniture stains.
Any valuables should be locked up of course. Who can you actually trust?
Keep the overnight bags in a public area.