Since Xbox players don't have the access to external cheats like the PS2, you will need to use a save exploit (requires an Xbox memory card, two controllers, and a lot of time) to get a load of money. You do jeopardize your saves by deleting some, so you need to be aware of what you are doing.

Step 1 - First you need to copy your save data from the harddrive to a memory card (which does not have MK DA savedata). Keep the memory card loaded.

Step 2 - Start a vs battle and load your profile for Player 1 as you would normally do. The game will ask you to choose instead of automatically selecting yours. Simply press A to confirm.

Load the profile for Player 2 and you will notice your own profile exists twice and can be loaded twice. You will automatically select the copy of the profile by pressing A.

Step 3 - Set a wager and then use the hanicap to lower player 2's health to 10%.

Fight the battle and player 1 wins the loot. Repeat as needed for the other Koin types. Once player 2 is completely broke go to the profiles screen and delete the broke profile.

Step 4 - Then quit the game and go to the Xbox Dashboard. Copy the save data from the Memory Card onto the harddrive. (Yes, overwrite the data.)

Then load the game again and repeat steps 2 trough 4. The more you do this the more money you can bet and the faster your koins will build up.

For beginning players this a great way to practise fatalities and earn easy money to unlock everything. I managed to unlock ALL the koffins less than a day.