How about rent increase matches property tax increase + inflation. If a property owner isn't paying fair taxes on its property value then rent isn't getting increased as well.
So assuming 2% inflation and maximum property tax rate increase of 2%, that would by 4%. Would a 4% increase be acceptable in your opinion?
In my opinion it's fair the have a rent increase if the property owner has a tax increase.
I see what you're thinking; a tax rate increase to the current market rate, as if it weren't locked in by that one California law (IIRC Prop 30?).