DOES IT COST TO FILE FOIA REQUEST ?
There is no filing fee for a subpoena, which is what an FOIA Request constitutes. You may have a service fee to properly get the Request served on the agency and the agency has the right to request the costs to copy the documents and the cost to retrieve the documents. Once service is complete, contact the agency and ask what the agency policies are for compliance.
There is no charge to make a Freedom of Information Act or California Public Records Act request. However, the government entity to which the request is made can charge reasonable fees for things like costs of research and copying.
Many government agencies now streamline the process and allow you to make FOIA/CPRA requests online. Check out the website for the government entity you are interested in and see if there is an online form on which to make your request. Otherwise, here is a link to a sample CPRA request letter: https://firstamendmentcoalition.org/public-records-2/sample-cpra-request-letter/
If you mean filing fee as far as my experience there is none.