They were never designed to handle today's water consumption (dishwashers/washing machines and 10 minute showers).

The same is true for smaller multi-family (5+ units) and even larger properties.Depending upon regulation in your area and the manner in which the property has been plumbed, you have the option of sub-metering water and billing each tenant for their actual consumption.  

We do not rent units with utilities included {students are not always careful with their energy consumption habits}, but we do provide a single payee option where the student tenants prepay their utilities through us each month along with their rent.  

Obviously different sized units and units with more or less tenants will have different consumption amounts.Hope that helps!

Tax consumption, not income.

Water is included for my duplexes, but I have a clause if the consumption goes over some dollar amount per month or quarter, it will be billed to the tenant.

They are responsible for consumption and thus should pay directly for that.  

If this is for your internal consumption, then go with what most folks are saying. 

Most people here are actually talking about how you deploy funds -- either for investment or consumption -- that the debt allows you to do. 

David the energy figure for your ADU is estimated at 2.8 KW, at $2.75 for each KW total is around $7700 with a 28% credit of $2150; net cost $5550.Here is what I have found on the California energy website:Moreover, the 2019 Standards require PV systems sized to offset just the annual electricity consumption of a highly efficient dual-fuel home.