Bathrooms, toilet rooms, and laundry rooms shall have a ceiling height of not less than 6'-8" above the finished floor"Additionally, in th following paragraph 1207.2.1; it also notes an exception for similar residential conditions which allows "Furred Ceilings" (Ductwork, Structural Beams, etc) to be permitted as low as 6'-4".In Short; the Diagram you posted indicates the correct conditions that would apply to your residential basement. 

we remodel the entire townhouse.

I have spent the last 8 years co-managing a small remodeling LLC, and have an primary background in project management, client coordination and admin communications/support. 

Including a flat fee for utilities on top of rent will make the rent look higher and less attractive to potential residents and potentially cost you money if there is a toilet running or water wasting.

At one point a plumber checking a toilet leak identified subfloor damage requiring the bathroom floor to be taken up and repaired.

I remodeled it and have it rented out now.

There's just too much damned inventory and too many people willing to price to the toilet to keep people in their places.

Most residential remodeling in all of CA is done without permits, long before this "housing crisis".

"Yeah, I'm just a guy like anyone else, so I have a private jet, forget the Lambo and solid gold toilet, whatever, there just things, I'm an average Joe who found out....". 

All the properties are occupied, but they need to be remodeled.