Here's an easy way to use the crafting system to make a ton of money when you're around level 10. Once you've got Gozen in the party and you've beaten the Demon Wolf, head to the crafting shop in Jade City. Buy a bunch of Hardbone Hilts and Steel Blades. You'll be able to use them together to create a Saber that sells for about twice the amount of the ingredients. Repeat to taste.
Even More Cash:
Around level 15, once you've gotten the forest pass, head through the forest to the next town in the swamp. Here you can buy Magic Blades. Combine these with Hardbone Hilts to create Darkswords that sell for way more than the Sabers described above.
Thanks to Revolution Readers sam and Tavasio!