There are three good ways to get some quick cash, but the one far into the game is by far the best. The first way : Selling treasures and fishing.
Treasures and fish can be sold, but only a certain amount of treasure can be obtained. When you meet Kokari in agata forest, after a certain mission you complete for him you will be able to fish there. When fishing, keep in mind it's best to go for the small fish. They may get you less cash, but they're much much quicker to catch than the big ones.
The second method is simply by quickly and taking no damage, defeating enemies around the Ryoshima Coast or North Ryoshima Coast area. It is not uncommon to get 6,000 yen from a good fight in those areas.
However, by a huge amount, the best place to get cash is in the Shinshu Fields very far into the game.
I will not ruin the story, but at this point, you can occasionally get 30,000 yen from one fight!
Added by: naraku2099 Oct 24th 2006, ID#23972