Legal is a hard thing to know here, honestly.
(People vs kelly) The supreme court threw out plant limits, so most folks, esp indoors do not worry about numbers so much.
If inside, just pay your electric bill and you will be fine. That is the biggest thing inside. Do not get a property near a school, church, daycare, etc....
The 99 plant scripts are not legal under California law, but I know guys who get them to sleep better at night.
But I also know of folks busted with 99 scripts and law enforcement loves to use the phrase of "He was growing illegally using prop 215 as a cover"
I suggest get a regular script, meet some nice friends that need meds and get copies of their scripts.
California counties typically recognize the 6 plant "rule" (which is a fallacy anyway) but because of that, if you have say 10 scripts of folks you actually know and LEO could verify if needed, then you can have 60 plants, etc...
but again, unless you are acting stupid, lots of traffic, etc, they should never go to your house if growing inside.
Do not keep scales or turkey bags or money counters or other drugs or guns......etc in the same place as your garden.
I know and agree that none of that should matter, but if you get a compliance check it WILL matter and you likely would be arrested.
I am full of advice so feel free to ask specific questions if you like and I will do my best to not steer you wrong!