The following tricks are for use as ways to expand the game and heighten it's playability.

More Difficulty Settings
Beat the game to unlock the hard difficulty setting. Beat it again, this time on the hard difficulty setting, to unlock easy difficulty.

Infinite Cash
At the Apple Market, kick the can into the bakery. You will receive 1000 Zenny from the woman behind the counter. Now, walk into any shop and walk back out. The can will continue to reappear. This will still continue to function when everyone leaves.

Unlock Bonus Parts
Beat the game on the hard difficulty setting within eight hours to unlock jet skates and buster max parts.

Gameshark Codes:

Enter these codes at your normal Gameshark screen.