All claims filed with the public entity shall be submitted within eighteen months of the date on which the claimant receives final payment for the property or the date on which he moves, whichever is later. The displacing entity may extend this period upon a proper showing of good cause.
Except where specifically provided otherwise a claimant shall not be required to submit a copy of his tax returns in support of a claim for relocation payments.
Cal. Code Regs. Tit. 25, § 6088