1. Kushner and Ivanka are not getting paid but are on staff as volunteers.
2. I doubt the Trump family fortune will even double (unless he is making deals before he leaves office, then he should have been impeached)
3.  Look at the % increase to the net worth Obama or the Clinton's gained once they moved to Washington.  Trump will not even double his net worth.
4.  But the one thing that I have noticed, politicians who become the leaders have loyal staff following them along the way whose career has depended on the politician.  As far as I can tell Trump took his secretary, his body guard and his daughter and son in law.  A year before the election no one else was associated with Trump.  I wonder if that is a factor in all the leaks.