Atlanta-area homeowners planning to rent-out their domiciles to Olympic visitors during the '96 games may have to add sales tax to the bill. The GA Department of Revenue is considering a proposal that would require visitors renting private homes to pay sales tax. In the past, GA Gov. Zell Miller passed a tax on private automobile sales that was ruled unconstitutional, and the chairman of the Southeastern Legal Foundation says this would be a similar deal. But Brian Kinsella, VP of the GA Hospitality and Travel Assoc., says the tax could be legal in situations where a third party sets up the rental. Private Housing '96, the official home rental service of the games, says that they, not the homeowner, will pay any additional cost due to the tax (Ben Smith, ATLANTA CONSTITUTION, 12/14).