There should be a Presidential Library in every state. Just for entertainment value of libs constantly protesting and trying to burn it down. And keep track of which one's they've torched.
President Zero actually didn't decide where to put his surprisingly controversial official library immediately upon leaving office. Hawaii wanted it, but the activists in Chicago demanded it be there. Naturally, they ended up bulldozing a predominantly black neighborhood to do it and handed the bill to Cook County taxpayers. Meanwhile, displacing block after block of residents. And it still isn't anywhere near completion.
President Trump could either just build one massive structure in Mar-a-Lago or just designate Trump Tower in Manhattan to be the site. It would draw interest especially in Florida and visitors from around the world.