California Code, Streets and Highways Code - SHC § 8682

(a) A copy of the order of the legislative body determining the assessments remaining unpaid and upon the security of which bonds are issued shall be filed in the office of the auditor. The auditor shall keep a record in his or her office showing the several installments of principal and interest on the assessments which are to be collected in each year during the term of the bonds. The auditor shall annually enter in his or her assessment roll on which taxes will next become due, opposite each lot or parcel of land affected in a space marked “public improvement assessment,” or by other suitable designation, the several installments of the assessment coming due during the fiscal year covered by the assessment roll, including in each case the interest due on the total unpaid assessments.

(b) The auditor shall also add a maximum of 5 percent of the amount of the installments and of the interest so entered, not to exceed the city treasurer's estimate of the expenses of collection, and in any case not to exceed eight dollars ($8) per lot or parcel per installment, except with the landowner's written consent. The expenses of collection shall include necessary administrative expenses of the city incurred in providing the auditor with current information regarding the ownership or division of the affected lots or parcels of land to ensure the proper entry by the auditor in his or her assessment roll of the several installments of the assessment coming due during the fiscal year covered by the assessment roll and the timely collection of the installments. The percentages, and the amount represented by the installments, when collected shall belong to the city and shall cover the expenses and compensation of the city treasurer incurred in the collection of the assessments, and of the interest and penalties added on to the assessments. No other percentage or amount shall be claimed by the legislative body for the collections.

(c) In the case of an assessment district created prior to January 1, 1988, the amount of collection costs which may be collected pursuant to this section may be the amount which could have been collected pursuant to this section as it read prior to being amended by Chapter 874 of the Statutes of 1986.