The city may elect to make a preliminary assessment for the local improvement at any time prior to completion of the project. The preliminary assessment shall follow the procedures for making the final assessment, except that the preliminary assessment shall not be levied by ordinance until completion of the project and the total cost of the local improvement is ascertained. Upon completion of the project, the city may make a deficit assessment or rebate as provided by Sections 13.16.210 and 13.16.230.