(1) In case of such election to pay in installments, the assessment shall be payable in not less than two nor more than twenty substantially equal annual installments or not less than four nor more than forty substantially equal semiannual installments of principal.

(2) Interest in all cases on the unpaid principal accruing from the date of publishing the assessment resolution upon its final passage until the respective installment due dates shall be payable annually or semiannually at a rate not exceeding eight percent per annum; except that, in the case of an assessment initiated subsequent to July 1, 1984, such interest shall not exceed the maximum rate fixed by the board in the notice of the provisional order hearing given pursuant to sections 32-11-608 and 32-11-609.

(3) Nothing in this article shall limit the discretion of the board in determining whether assessments shall be payable in installments and the time the first installment of principal or of interest, or of both, and any subsequent installments thereof shall become due.

(4) The board in the assessment resolution shall state the number of installments in which assessments may be paid, the period of payment, the rate of interest upon the unpaid installments of principal to their respective due dates, any privileges of making prepayments, and any premium to be paid to the urban district for exercising any such privilege, the rate of interest upon unpaid principal and accrued interest after any delinquency at the rate of one percent per month, or any fraction thereof, and any penalties and any collection costs payable after delinquency.