A twenty day preliminary lien notice is necessary in the event you want to record a mechanic's lien or file a stop notice. You can still file a lawsuit directly against the contractor for breach of your contract. I suggest that you consider filing a small claims court action over what you believe is owed to you. A good book that will help you with the process is "Everybody's Guide to Small Claims Court" by Nolo Press. You can get the book at www.nolo.com.
The failure to file a 20 Day Preliminary Notice probably eliminates your lien rights against the owner, unless you can prove that he/she had actual knowedge of your subcontractor releationship. Youcan still sue the GC without a 20 day Preliminary Notice.
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