Senate Bill 644 amends provisions of the Civil Practice and Remedies Code and Tax Code relating to a tax sale of real property. The law requires a person, for the person to be eligible to purchase real property at a tax sale, to obtain from the tax assessor-collector of the county in which the tax sale is being conducted a statement declaring that the purchaser has no delinquent local ad valorem taxes. This bill exempts a tax sale of real property in counties with a population of 250,000 or less from the provisions unless the county commissioners court has adopted the provisions requiring the purchaser to obtain the statement.