The police are likely to consider your dispute a civil matter and, thus, not do anything.
If CA courts have jurisdiction over the company, you can bring a small-claims action for the excess amount you are forced to pay. If not, then, unfortunately, as a practical matter you are unlikely to have any effective remedy.
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These are problematic. First, it is really a civil matter and not criminal. You are unlikely to get much help from the authorities. Second, the amount in dispute is not so much that you can afford to hire an attorney to assist in this matter directly. You could pay them, obtain your property, then attempt to get the overpayment back through a small claims action.
There is one other way to look at proceeding. There have been numerous states that have attempted to get these unethical practices by moving companies to stop. I would presume, due to the large number of citizens, California may be one of these states. It might we worthwhile to contact an attorney at the Attorney General's office to see if they have any knowledge on how to help you. I know some moving companies have been sued in Class Actions on this point, but I simply do not recall the details.
Best option is to pay it, and get your stuff, then worry about what to do next. Be sure to tell friends and family what they did. Contact the Better Business Bureau and the Chamber of Commerce where they do their work from. You might be surprised at some of the results you might get. Good luck.
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