For one who likes trading games like monopoly what's the closest 2-player game with similar dynamics?
How about Traders of Genoa?


  This is a game of trading, wares, and negotiation. The players take
  the roles of traders in Genoa in the 16th century. They fulfill
  orders, deliver messages, and take ownership of buildings in the city.
  Of course, this is not possible without the help of the other traders
  - thus, the need for clever negotiation. And that can cost money and other valuable goods! The player who earns the most in the game is the
  winner! 


http://riograndegames.com/Game/200-Traders-of-Genoa

It's a fair amount more complex than Monopoly, but much less random and there's a lot more negotiation and trading involved. It plays with two, although it is better with more, much like Monopoly. It'll probably take about 90 minutes to play to completion with two.

Currently officially out of print, but you shouldn't have too much trouble tracking down a copy. It's sometimes known as "Genoa" rather than "Traders of Genoa" but it's the same game.