Infinite money: 

At the title screen, press L1 + L2 + R1 + R2, then 
press Square + Triangle + Start. The map selection
screen will be displayed. Now hold L1 + L2 + R1 + R2
and press Circle. If you entered the code correctly, 
you will hear a sound. Pause the game and press Left, 
Right, Up, or Down to gain more money.