According to this, he isn't doing all that well.
There's just one question: How is Donald Trump—the businessman, not the TV star—doing these days? The answer seems to depend on which part of his empire you're talking about.
Examine the performance of Trump's one publicly held company—the casino business—and it's clear that taking your business cues from The Donald is far more likely to lead to fame than to fortune. Once the major source of Trump's nearly billion-dollar wealth, Trump Hotels & Casino Resorts has lost hundreds of millions in market value since going public in 1995. Trump's personal stake—he controls 56% of the company—is worth just $41 million, down from more than half a billion dollars in 1996. The humbled gambling company, whose marquee property is Atlantic City's Taj Mahal, is so burdened with debt—$1.8 billion in all—that it's draining cash. Trump himself admits that he's considering restructuring the debt, perhaps by bringing in new investors, even if that meant he'd give up some control. He notes that "every institution loves me."
Trump strikes me as one of those people with confidence to the point of it being a personality flaw. Too much confidence leads to cockiness, and then you get blinded to the arguments of naysayers and end up making bad decisions sometimes. Maybe whoever the apprentice turns out to be can help Trump turn things around.