(a) The tax collecting authority shall proceed to advertise the lands and tenements of the taxable by posting handbills in at least 10 public places in the county, 1 of which shall be on the lands to be sold, and 1 at the courthouse, and by publishing the notice or advertisement of sale in a newspaper of the county at least 1 issue before the day fixed for the sale. All sales shall be made at the courthouse door and the handbills and advertisement shall contain the day, hour, place of sale, and a short description of the property to be sold.
(b) In case the owner of any lands and tenements against which a tax shall be levied and assessed is unknown, this fact shall be stated in the advertisement of sale, and in addition to the notice herein required, the advertisement shall be published in some newspaper published in the county in at least 2 successive issues thereof before the day fixed for the sale of the property.
(c) The tax collecting authority shall keep a record of the places where the handbills were posted and of the newspaper in which the advertisement was published, and such record shall be presumptive evidence of such advertisement and posting.