Note: The following tricks required an unpatched version of the game.

Throw the weapon that you want to duplicate. Before it hits the ground, press Up. Then, choose to drop the weapon that is equipped. Exit out of the menu and pick up both items. Repeat this as many times as desired. Sell them for easy money.

For example, if you have a "Deathstalker Zed's Demise" worth $7,350 and if Jin is available, empty your inventory save for the sword into storage. Go to the nearest shop. Once there hold L1, then hold Triangle and press R1 to throw not just one weapon but two. Pick up the discarded weapon and repeat the process. Sell all but one of the copies of the weapon for easy money. Doing this can also copy "sticky bomb knives", though occasionally one of the bombs will explode. Note: This does not work on grenades, guns, or building materials.

Note: This trick does not work with projectile weapons. Hold L1 then hold R1 + Triangle. If done correctly, there should be two of the same weapon on the ground and it will show that you threw and dropped the same weapon. This can be done as many times as desired. You can use this trick to make money in game or in online play, and you can supply teammates with powerful weapons. You can also duplicate a weapon instead of repairing it. Note: This also works with modified and upgraded weapons.