If we will be doing work for a home owner, do we still have to send prelim notices?
Generally, in California, direct contractors (i.e. those hired directly by the property owner) are only required to send a preliminary notice to the construction lender; if one is present on the project. Otherwise, no preliminary notice is required to secure mechanics lien rights.
Keep in mind, however, that there is certain notice language and other requirements for California home improvement contracts.
If you directly contract with the owner, you don't need to serve a 20-day prelim on the owner because the owner is already on notice of you. If there is a lender, serve the lender though. Good luck.