Many if not all of the recent and living presidents have used the whole 'Presidental Library' grift as a way to bypass the emoluments clause. More recently they've used 'Charitable Foundations'. Nothing has ever really been done about it for the last few folks to hold the office. Maybe because it's Trump this time, we can get some serious reform to this form of naked corruption. I expect him to go big on the library / foundation grift.