The lien for delinquent assessments shall include the district's and treasurer's costs attributable to the delinquency and interest at the rate of twelve percent per year, computed monthly and without compounding, on the assessments and costs. The word "costs" as used in this section includes all costs of collection, including but not limited to reasonable attorneys' fees, publication costs, costs of preparing certificates of delinquency, title searches, and the costs of foreclosure proceedings.