If I can help it,I only buy units with all utilities paid by tenants.
When I started out,I got an older duplex with a shared meter.
Have not repeated the mistake since then.
6 months ago,water bill at that unit jumped from 45$ to 2000$-in one month.Then it stayed that way for three billing cycles before I caught on to it.
Turns out the neighbor had connected a hose pipe to the backyard pipe while tenant was away and started running a car wash on my dime.
When informed,tenant was essentially nonplussed.Not her business.
I will now be having the meters separated at some heavy cost,but will have lasting peace of mind.
If she got the 2000$ bill in her name instead,she'd show some more responsibility perhaps?
I just hate surprises.
Are you sure the tenant doesn't know more than she let on?
Seems like you should be able to call someone....like the water dept or police or something to hold the other people accountable.
If the bill was in your name, did you not open the bill?
If you have proof that the neighbor did it, I would call the police and file criminal charges
In the meantime try no outside spigots ?
I also have a clause about excessive use charge back I would use in this case. In any event I would give your tenant a lease violation if I could find one that applied.