ADU - splitting existing SFR

[Angela Zaitz]

There was a sun room that was added to the house and I’m planning to  have that finished ( insulated and dry walled and vent added) and use that as great room and add a wall to enclose the  kitchen to access  the back unit which  will have have access to 1 bedroom.  

I will add kitchenette to great room of front unit and there will be no common areas.  i plan to live in back unit and rent out front. I know I will have to split the utilities, and will add solar to offset electric costs. 

Will there be an issue with permitting for ADU? I have read that an ADU need separate water heater? I'm not sure how I could split any of the utilities. Any suggestions or tips ?