Legal Question in Real Estate Law in California

If the notarized instrument you hold is a mortgage or deed of trust, you can file (record) it with the County Recorder in the county where the property named in the deed of trust or mortgage is situated. If your notarized paper is just an IOU (promissory note), obtaining a lien on the person's home is a multi-stage process that starts out with filing and winning a lawsuit against the person for breach of the agreement to repay you; then you can record an Abstract of Judgment which will have the effect of creating a lien.

There is only a limited number of ways to place a lien on soneone else's lawsuit. It is easier for contractors and suppliers for improvement projects, because they can record so-called mechanic's liens (although often they are not "mechanics" in the modern sense).

Notarizing an ordinary IOU does not make it recordable. In fact, with most home loans, the lender records only the deed of trust, not the promissory note.

If you have a Trust Deed from them like you should, then it could be recorded to create a lien. If you simply have a promissory note or other documentation proving the debt, then you could do so by suing and winning a judgment. Feel free to contact me if serious about getting legal help trying to get your money back.