Actually, there is no cost to this and you can do it on your own, or have an attorney. Once you have a judgment against someone, you can ask that the debtor appear in court to answer questions under oath. This is called a "debtor's examination," and you can ask the debtor questions about his or her assets or property. You can ask about things like where he or she works, how much he or she earns, bank accounts, stocks, other income sources, property and belongings, and anything else that can be used (or sold) to pay the judgment.
You can also subpoena the debtor's paycheck stubs, bank records, deeds for any property he or she owns, and similar documents that prove the existence and value of the debtor's property. At the debtor's examination, you can ask the judge to order the debtor to turn over any assets the debtor has with him or her at the time, like the cash in his or her wallet, for example.
This portion of the California courts website will provide you with the necessary forms to request a debtor's examination and/or to subpoena information. http://www.courts.ca.gov/11187.htm
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