For example, the author writes about how Turkey seriously contemplated offering Trump "an enviable hotel site on the Bosporus" to curry favor with him. If you're not super familiar with that country geography, the Bosporus is the strait between the Mediterranean world and the Black Sea. Prime coastal real estate along that waterway is highly desirable and hard to come by.
This speaks volumes for how the world sees Trump: easily corruptible with a primary interest in helping himself. Trump was already in a real estate project in Turkey before the election which, in a 2015 radio interview, he admitted represented a conflict of interest should he become President (details here).
"I have a little conflict of interest, because I have a major, major building in Istanbul," Trump said, referring to the country's capital. "It's called Trump Towers. Two towers, instead of one. Not the usual one, it's two. And I've gotten to know Turkey very well."
Another interesting revelation in Wolff's book is the fact that Trump's former senior adviser Steven Bannon and his attorney general Jeff Sessions are very close and in regular contact. Trump has long had an enmity toward Sessions, notwithstanding this was his first cabinet pick, because of the attorney general's recusal from all aspects of the Russian investigation.
Since publication of the book, the President has burned all bridges between himself and Bannon and famously excoriated his one-time ally on Twitter in the media. Both Bannon and Sessions are known to be devious plotters and score settlers and both have every reason to betray Trump now.
Special Counsel Robert Mueller, who is conducting the criminal investigation into Trump and his associates, is known to have questioned Sessions recently as part of his probe (details here). Given Sessions faces the possibility of being charged with both perjery and obstruction of justice, he would have a clear incentive to testify against Trump if offered a plea deal in return for cooperation.
Mueller will also question Bannon, possibly by the end of this month or shortly thereafter (details here). While Trump's former White House advisor was apparently out of the loop on the campaign's Russia collusion, he has promised to tell everything he knows if called before a grand jury.
Sessions and Bannon undoubtedly continue to talk and, possibly, plot against Trump together. By alienating two powerful former allies who now have more strength together, the President has once again proven to be his own worst enemy.