council decis decemb authoris republ austria appli measur derog articl sixth direct eec harmonis law member state relat turnov tax ec council european union regard sixth council direct eec harmon law member state relat turnov tax common system ad tax uniform basi assess articl thereof regard propos commiss letter regist commiss secretariat gener decemb austrian author request authoris appli special measur derog articl direct eec member state inform request march derog measur intend complet exclud ad tax vat charg expenditur good servic deduct good servic privat purpos taxabl person employe gener busi purpos derog measur repres derog articl justifi simplifi levi vat durat authoris limit decemb maximum period evalu made advis maintain derog measur light austria experi period derog measur neg effect commun resourc vat adopt decis articl derog articl direct eec republ austria authoris exclud expenditur good servic deduct vat good servic privat purpos taxabl person employe gener busi purpos articl decis appli decemb articl decis address republ austria brussel decemb council presid bot oj direct amend direct ec oj