(1)Any improvement expenses under section 500 shall be a charge on the premises in respect of which, or for the benefit of which, such expenses are incurred, and shall be recoverable in such installments, and at such intervals, as may be sufficient to discharge such expenses with interest thereon at such reasonable rate as may be determined by the municipality from time to time, and within such period, not exceeding thirty years, as the municipality may in each case determine.
