At about 1:17:30, when Jorgensen meets with the woman from Leviathan, the large painting of the sailboat hanging on the wall is Rembrandt's "Christ in the Storm on the Sea of Galilee". It was stolen from the Isabella Stewart Gardner Museum in Boston on March 18, 1990.
The bar in Brussels where Cyrus meets with Harry is actually the Crown Liqour Saloon in Belfast, Northern Ireland; one of the oldest bars in Belfast and famous for its layout of small private booths, where the conversation between Cyrus and Harry takes place.
At $2000 an ounce, $500 million gold would weigh 7.8 tons.
This movie bears some similarities to "The Italian Job" movies. The all begin in Venice with a boat chase and the main heist is stealing bars of gold.
As the first jet tries to brake on the runway, you can see the brakes getting red hot from the friction (a nice detail in the CGI).