Lately I have been building the Forbidden Palace to enjoy the significant drop in city maintenace that results. What I am not clear on is whether I continue to benefit from the FP after I switch into State Property. If so, then whether to build this National Wonder is very situationaly dependent. If not, and my civ has grown to a respectable size, then it would almost always be the thing to do. Also, are there any differences in effect between Versailles and the FP?