Legal Question in Employment Law in California

You can always put a lien on a home, the issue is how and whether it would be valid. Mobile homes are different from fixed buildings. Different rules apply. If you don't have a contractor's license it would be illegal for you to record a lien against a fixed building, but it may be legal for a mobile home since I believe it is not a "work of improvement." You also probably have to file the lien with the DMV like a mechanic on a car, rather than at the county recorder's office. I recommend you start with the DMV and see what they can tell you.