I think Trump will mostly likely become the next Sarah Palin. He’ll set up a phoney PAC, hire his family, do business with his own companies, let fringe candidates treat him like a king maker, and do lots of paid appearances on Fox News. There will be a few more books. Eventually he fade out when someone even crazier comes along.
He's already doing business with his own companies. Pretty much every resource his campaign is using (plane, offices, etc) are being leased from Trump industries. He's using campaign contributions to pay himself.