Start up your game, then go south a screen to Freedom Hill. See the four piles of gold? Collect them, then go north a screen (to where you started), enter the tent, and save. Once you've saved, soft reset (Start+A+B+C), then load up your file and go back to Freedom Hill. The gold will have reappeared! Each run will earn you a little under 200 gold, and you don't have to fight a single monster!