Confidentiality. The returns filed by taxpayers, and the records and files of the Chief Financial Officer respecting the administration of the transfer tax and user tax, shall be considered confidential and privileged, and neither the municipality nor any employee or agent engaged in the administration thereof or charged with the custody of any such records or files, nor any former officer or employee, nor any person who may have secured information therefrom, shall divulge, disclose, use for their own personal advantage, or examine for any reason, other than a reason necessitated by the performance of official duties, any information obtained from the said records or files or from any examination or inspection of the premises or property of any person. Neither the Chief Financial Officer, nor any employee engaged in such administration or charged with the custody of any such records or files, shall be required to produce any of them for the inspection of any person or for use in any action or proceeding except when the records or files or the facts shown thereby are directly involved in an action or proceeding under the provisions of the State Uniform Tax Procedure Law or of the tax law affected, or where the determination of the action or proceeding will affect the validity or amount of the claim of the municipality under the tax provisions of this subsection.