Good question.
Lie, shame and be ready to be firm.
Communication is key. Emphasize green. Emphasize in your listing "green household"
We recycle, we conserve. We love salmon. We are the world.
Emphasize Reasonable showers only.
Do you know that 2 showers a day kills Eskimo children in The Yukon and bedoins in the Sahara?
Do you know that your city penalizes us for high water consumption? Please be considerate so the guests at the end of the month can have water for their showers.
If you don't recycle, the city will not pick up our trash.
In other words, be clever. Try to lift up your guests' consciousness.
Try not to attract abusers. "No shaving in shower" "Spa is down the street"
"Water abusers will be asked to leave"