(a) Compensation required under the provisions of Sections 23-1-280 and 23-1-281 shall be paid to the person or persons entitled thereto. If the director and the owner or owners reach an agreement on the amount of compensation payable to such owner or owners in respect to any removal or relocation, the director may pay such compensation to the owner or owners and thereby acquire or terminate his rights or interest as by purchase; provided, that any sign, display or device lawfully in existence along the interstate system or the federal-aid primary system on February 10, 1971, which is not in conformity with the provisions contained in this division shall not be required to be removed until just compensation has been paid therefor. Notwithstanding any other provision of this division, no sign, display or device otherwise required to be removed under this division, for which just compensation is authorized to be paid by the director, shall be required to be removed if the federal share of at least 75 percent of the just compensation to be paid upon removal of such sign, device or display is not available for such payment.

(b) If the director and the owner do not reach agreement as to such amount of compensation, the director may institute an action to have such compensation determined in a civil action. Such an action shall be instituted by filing a petition in the probate court of the county where the advertising device and land are located. Such action for determination of compensation shall thereupon proceed and be treated in accordance with the provisions of this title and Title 18 of this Code to the extent not inconsistent with the provisions of this division, the same as if such action had been commenced thereunder by a petition by the state for the taking of property under its power of eminent domain.