To assist in the keeping of the tax books, the collection of taxes, the remitting of funds to pay maturing bonds and coupons, and to be of such other service in the general management of the affairs of the district as may be determined, the board of drainage directors has authority to appoint a fiscal agent of such district. Any drainage district may purchase any lands sold within the district to pay the delinquent assessment on the lands, if the board of directors deems it advisable to do so, and the board of directors may sell such land so bought and make a good deed to the land.