Section 249.520 - Contractor's bond - apportionment of costs - assessments - tax bills1. The contractor to whom such contract is awarded shall enter into a contract with the county commission and shall furnish a corporate surety bond to be approved by the county commission in an amount set by the commission and at least as much as the amount of the contract.2. When the terms of such contract have been completed under the supervision of the sewer engineer, said engineer shall compute the cost thereof, including necessary engineering and clerical expenses, certify same to county clerk who shall then proceed to apportion the same against the lots, tracts, or parcels of ground in such sewer district or districts calculated according to one of the following: (1) The square footage in proportion to the area of the whole district;(2) The lineal feet of sewer line running along or through the property for each lot, tract, or parcel of ground in the sewer district, exclusive only of public highways and parks; or(3) By determining the total number of lots affected and apportioning the cost equally to each lot; and shall report the same to the county commission. Upon presentation of the report of the sewer engineer the county commission shall levy an assessment in accordance therewith against all the land except public highways and parks in the sewer district or districts, and shall issue special tax bills to the contractor in payment for the work.3. In case the owner of any land described in any such tax bill files a request with the county clerk prior to the acceptance of the work by the county, requesting that his tax bill or bills shall be made payable in equal installments, or in case the county commission determines that it is advisable that they be paid in installments, such special tax bills shall be payable in annual equal installments from two to ten years after the date of their issue, as the commission deems warranted under the circumstances. The whole of any such special tax bill made payable in installments may be paid at the date of any installment payment.4. Every certified tax bill, whether the same be made payable in installments or not, shall bear interest at the current rate per annum as approved by the county commission from the date of issue until paid, but may be paid without interest within thirty days after the date of issue, and shall be a special lien against the property described therein for a period of five years from its date, except for when payable in installments, when the special lien shall extend for a period of one year after the date the last installment payment shall become due. Every such certified tax bill shall be assignable and shall in an action brought to recover the amount thereof be prima facie evidence of the validity of the charges against the property therein described. If such tax bills are not issued in installments as provided in section 249.530, they shall become due and payable thirty days after date.L. 1941 p. 557 § 8, A.L. 1983 H.B. 371, A.L. 1997 H.B. 159