In California a landlord can raise the rent in any amount unless they live in rent controlled community like San Francisco, Berkeley, and some others. Most of California does not have rent control.
If the amount of the increase is 10% or less, the notice need only be 30 days. If the amount of the increase is more than 10%, the notice must be 60 days. If the landlord gives more than one increase in a year, the notice would have to 60 days when the cumulated rent increase totals go over 10%.
The notice should be served at the tenant's and a copy mailed. This is proper service.
Most landlords give 3% increases on an annual basis when single family dwellings are the subject. Much more and you are inviting your tenant to pack up.
I would suggest that landlords and property managers do a rent survey prior to considering a rent increase so you know what the tenant will be looking at when the increase arrives.
The greater Sacramento Region, including Sacramento, Yolo, Placer, and El Dorado Counties do not have rent control.