The Tax Assessor shall assess all real property to the person who is either the owner or in possession of the property as of January 1, and the person appearing of record as of January 1, shall be held to be the true owner thereof, starting with the FY 2013 bills, and similarly following each year thereafter. Except as otherwise provided, all taxes must be assessed as of January 1 of the calendar year with respect to which the taxes are assessed. Property characteristics and assessments are as of January 1 for the Calendar Year of which tax bills are issued. No deduction shall be allowed on account of any debt incurred by mortgage, conditional sale, contract, or other obligation upon said real property and the taxes so levied shall be a lien upon the property.