Laundry Use Clause in Lease

[Francesco G.]

I have a fourplex where each tenant has their own sink and separate hookup for a washer and gas dryer in the basement that they would have to provide.  I pay for the water as there is only one meter on the property but the electric and gas are all metered to their units.  My water bill is fairly low, about $100-$120/month with 6 adults and 2 children in the building.  

For anyone with tenant provided laundry machines, what kind of clause do you have in your lease for laundry use?

I've thought about coin/card operated machines but don't want to be receiving calls every time they breakdown.