We discussed the deal that Lauria and Sater allegedly made with the federal government to try to purchase stinger missiles from Osama bin Laden - missiles the CIA was the ultimate source of and which the CIA wanted back. This was not long before 9/11. The deal fell apart. According to the book Lauria and Barry co-wrote, after 9/11 the federal government got a lot more interested in what Lauria and Sater might have to offer, not surprisingly. That was at the start of roughly eight more years in which Sater worked simultaneously both as an FBI informant and - for most of the time - a key business associate of Donald Trump's. Here's a backgrounder on Sater. This post also goes into details about his background and his business relationship with the President.
Sater remains a very interesting person for Trump to have been in business with.