Upgrading to better weaponry in Final Fantasy 13

[DragonLord]

Keep in mind too that certain items are meant to be "currency" only.  They are worthless for upgrading, but bring good value for selling.  Examples are Incentive Chips and Credit Chips.  Farm for them and sell them (only thing they are good for) and they bring you good amounts of gold.  Then use the gold to buy 36 Sturdy Bones and sell them for a 3x Exp. multiplier.  Then use organic items to wrack up massive amounts of experience--but sell a ton at a time because your experience multiplier drops each individual time you sell an item.