This is the problem of shared bathrooms.
Communal = Shared responsibility = Blaming others = Passing the buck.
No one believes that they are the ones who leave hairs - It's always someone else's problem.
It is what it is.
Yes, you can put up a sign: "Bathroom cleaned daily. For everyone's consideration, Please clean up after use"
You can provide cloths to wash down/dry surfaces after use.
You can ask guests to not leave their stuff on the bathroom counters.
But it is what it is. Although guests like the pricing that goes with shared bathrooms, they don't like the problems that come with shared bathrooms.
I try to "hit" my shared bathrooms twice a day. NOT to do a deep cleaning, but just to wipe down hair/surfaces, clear out garbage and shine the chrome. 3 minutes tops.