On April 1, the listers shall proceed to take up such inventories and make such personal examination of the property that they are required to appraise as will enable them to appraise it at its fair market value. When a board of listers is of the opinion that expert advice or assistance is needed in making any appraisal required by law, it may, with approval of selectboard or by vote of the town, employ such assistance.
32 V.S.A. § 4041