1. People have mentioned rent control -- the state-wide law is 5% + inflation rate per year. This is pretty generous/good as a landlord and I'm fine with that. That said, local municipalities may have their own more strict rules (eg San Francisco)
2. Emergency declaration anti-gouging laws can be a problem as they limit rent increases to 10% the time the emergency was declared. In parts of Northern California, the declaration from the 2017 fire is STILL in place. And frankly I don't see this declaration going away. But in my mind something needs to be done about that legislation.
3. New state law has also limited evictions to 'just cause' only. So they need to be breaking their lease. That said, I'm not sure what happens when their lease is over. If you want to kick people out for renovations (a common reason in the past) you need to pay them relocation money, not sure of the amount but I remember 2 months?
If I didn't live here, not sure I would have rentals. Cap rates are really low compared to other states where I"m invested. That said, it is so much easier for me to rent when I have a vacancy -- I only have a day or so between tenants which is used for cleaning.
Good luck!