In Alabama, a retailer selling highway construction supplies and devices tax-free to contractors doing contract work for the Alabama Department of Transportation was found liable for sales tax. The items sold included permanent and temporary signs, barrels and cones, flashing lights, safety vests, Gatorade, and batteries. The taxpayer believed that all items sold would be “incorporated into realty” thus making them nontaxable. However, the auditor explained that items used in a temporary capacity must be treated differently than those items sold to be permanently attached to realty. In Alabama, it is the taxpayer’s “affirmative duty to investigate and determine if each of the items were intended to be incorporated into realty, and thus exempt.” The taxpayer also made some cash sales to “government employees who were buying for the federal government”. Unfortunately, the taxpayer had no record of these sales, thus making them undocumented cash sales subject to tax. (Safety Guide of Alabama, LLC v. State of Alabama Department of Revenue, Docket No. S. 03-412, February 3, 2004)