Without a doubt, all landlords have become familiar with the legal matters involved in providing rental units through experience. To freshen up on the facts, and to learn them from scratch as a new landlord, the California Department of Consumer Affairs landlord and tenant information section is imperative.
This article from Investopia regarding becoming a landlord discusses many topics like: Appreciation, Leverage, Tax advantages, Liabilities, Expenses, and Vacancies. It's mostly common knowledge to an experienced apartment manager.
This article about the Roles of a Landlord includes some useful links like: How to run a credit check, and how to maintain the property.