To be eligible to bid at the tax sale, you must have an unexpired written statement (Form 50-307) from Lubbock Central Appraisal District that you do not owe delinquent taxes in Lubbock County. Tex. Prop. Tax Code Sec. 34.015. You will not be allowed to bid if you do not present this unexpired Statement of No Delinquent Taxes Due when you register. You must register in order to bid.