Auxiliary meter for splitting water bill for duplex

[Kristina Inglis]

Hi, 

Has anyone out there used a water auxiliary meter to create a separate measuring system for a duplex?   An auxiliary meter breaks out the water usage between 2 units based on their individual use of water.  The purpose is to be able to transfer the cost of water use from the landlord to the tenant.  I'm wondering how much of a hassle is it to calculate and bill the tenant each month and if there are any other things I should consider before I install one.    If anyone out there uses one of these to bill their tenants for water, I'd be very appreciative of any feedback you may have based on your experience. 

Many thanks,

Kristina