To get this achievement you need to collect 50,000 gold on a single playthrough. It doesn't matter if you spend the gold, and buy and rebuy items.
This will come naturally, I am sure. HOWEVERIf you need this done quickly, and you are in favor of farming.... please read on.
This method will allow you to get this quickly, and soon after you get access to the war table.
Before you start:You need to have access to the mission where you collect gold. (It is on the left side of the Fereldan side (the right card)) .
1.Save before you enter the war room.
2.Close the game.
3.Go into settings and disconnect from the internet. (go offline)
4.Hard power down your console (hold on the light on the console until it powers down)
5.Turn on the console again.
6.Go into settings and change the year to: 1916 (assuming you are in 2015)
7.Load the game and continue.
8.Enter the war room.
9.Select on the GOLD money mission - choose the character.
IT SHOULD AUTO COMPLETE GIVING YOU THE MONEY AND COMPLETING A MISSION.Do this a whole bunch more times. You will have to count yourself since the acheivements cannot be tracked while you are offline.
When you are satisfied, close the game down (don't just minimize it - close it) and go into setting and go online again. Then you load up the game if you have done the 50 missions the achievement will pop around the title screen.
NOTES/CAUTIONS!!!!!!- For me when I was doing this, the QUEST WORLD MAP was a bit screwy and the cursor would have a hard time going where I wanted it to go. When I went back online, the problem was fixed.
- If you use a turbo controller (as I tried), the game will crash. At least it did for me.
- I would recommend you exit the war room every so often to make sure you save.
You can also use this solution for:Because if you are like me you will probably do this at least 1000 times and get more than 100,000 gold.
If you need something to buy because your level is too low, install the black emporium and there are accessories in there for 7000-15000 gold which are rare purple and can be equipped on lower level characters.
Not to mention you can complete requisition quests by buying the ingrediants there. Not all of them, but some of them.