A friend of mine has been working on this same angle since Trump was elected.

Politico covered his work in August:
http://www.politico.com/story/2017/08/20/trump-bombshells-ro...

His website is here: Weird money in, weird money out
https://ragepath.org/weird-money-in-weird-money-out

And below is his working hypothesis:

We've documented Trump's relations with a variety of Soviet and Russian individuals and organizations in the attached bullet book. Financial crimes and money laundering explain a large part of Trump's wealth.

Trump's basic grift seems to be one that he learned from his father. A loan is just a tax-free transfer of cash. So don't pay yourself income when you can loan yourself cash instead. Whether it's embezzled FHA mortgages, Mitchell-Lama funds, NJHFA funds.... it doesn't matter. Borrow way more than you need, live off the borrowings, use the loan payments to offset gains from other legitimate sources of income.

40 Wall Street in NYC would be a great example of this. Trump bought the building for $1 million cash in the latter half of 1995 (a time of many highly suspicious cash transactions for a man who was allegedly $900 million in the red). He borrowed $35 million supposedly to renovate it (maybe). Let's imagine that it loses money, let's go wild and say it's losing $1 million a year (an overestimate) for 20 years. Overall, Trump's out of pocket by $56 million. But he's borrowed $160 million against the building. That means his net cash position is $104 million. And many of his deals are structured in a similar way.

This looks to us like a classic money-laundering scheme known as a "loan-back." Let's say Trump's brother Robert loans a company $500k which it then uses to open up a $5 million account offshore (Financial Performance Corporation) and another company affiliated with Robert (Management Technologies) spends nearly $13 million buying a shady group of international companies called Winter Partners... which Midland Associates (a Trump family partnership) then loans an unknown sum secured against all their future accounts receivable. Management Technologies would later write off its Winter Partners investment as a complete loss.

So we can show that Robert Trump was shoveling money overseas in 1995. And just when Trump needed it, investors from Hong Kong showed up and bought the mortgage on Riverside South, overing him insanely generous terms. When they sold the mortgage later for a billion dollar profit, Trump freaked out (even by his standards) - a reaction that makes more sense if you realize that the loan was originally Trump's money, and the Hong Kong investors were only supposed to act as nominees. After they cashed out their profit, they ended up selling their 70% stake, which found its way into the hands of Trump's friend at Vornado Realty, Steve Roth.

So that's the core of the insight we've had. It's an explanation that seems to hold up well when we examine individual deals that Trump's been involved in. So many of his ventures lose money because the loans themselves are just part of a money laundering show - a tax free way to legitimately receive a pile of cash you're not otherwise entitled to. And the lender has access to an offshore asset as security, so even if you eventually default, they'll be made whole. We're not sure how much of it is Trump's money.

Here's a quick dash through the overall timeline of Trump's life that we think we see:

1974-1987: Trump comes up in New York real estate rubbing elbows with various mobbed up figures (Cohn, Salerno, Tomasello, et al.) and working as a kind of front man for the Genovese, Gambino and Scarfo crime families. A lot of his early projects are just classic mob grifts. Borrow a bunch of money to build something, hire a bunch of mob contractors, pay too much... Trump's being taken care of but not enormously so

1988-1990: Trump borrows $3 billion in the course of 2 years, $650 million of which is mean to finish construction of the nearly completed Taj Mahal. Within two years the money is gone, despite the fact that many of the construction contractors hadn't been paid. So this is the period where we think Trump embezzled the money, got a cut, and had to hide it offshore until the statute of limitations had cleared.

1991-1995: Trump's laying low. The Soviet Union collapses. Tamir Sapir, Sam Kislin, Eduard Nakhamkin ... three (at least) Russian figures suddenly leap from working-class Russian immigrants to international financiers in control of huge sums of money. Our working theory is they were ex-KGB, after the Soviet Union's fall they began collaborating with American counter-intelligence officials at the FBI and CIA, and they used their positions in New York to help their former associates back home embezzle billions of dollars in state-owned assets out of the former Soviet Union.

1995-2005: Trump begins repatriating his own money in some of his most bizarre business deals. Trump perhaps realizes he can syndicate this model and also begins facilitating loan back schemes for Russian investors by putting his name on their buildings (the whole Bayrock period)

2006-2015: Most of Trump's money has come back to him by now, and he's basically running a money-laundering syndicate for Russian oligarchs (though there are still some Italians and Asians in the mix) - some of whom are in favor with Putin and the state, others who are decidedly not.

If we're right, it's an audacious scheme that he's managed to pull off right in front of our faces. He's managed it by exploiting our preconceptions about debt and net worth. All the fights over Trump's wealth have been about his net worth - what's the value minus the liabilities? And we look at a debt as a zero-sum transaction. But the Trump enterprise really seems to be operating on net cash flow.