The laws vary from county to county, and town to town.
I don't know much about LA, as most of my squatting has been done in the bay area.
However, what you seem to be mentioning is "Adverse Possesson," which in California does mean
five years of occupying the property plus paying the back taxes.
That means occupying it without being evicted by the police or the landowner and paying all the backtaxes to the tax collector at the administration building or courthouse for that
particular county.
From my understanding, finding a good house for adverse possession means finding one owned by a trust, or a dead person whose deed is still in that dead person's name.
However, if you are not wanting to make that much of a commitment, you can occupy an abandoned house, get mail and utilities in your name, and then whoever has to evict you will have to go through an eviction process because at that point you are legally a tenant.
Oh yeah, that guy in that video is a good friend of mine.
Here is his blog which might be more helpful then me.
blogsquats.blogspot.com