Successfully complete the game in under three hours to unlock the Easy difficulty setting. Alternately, successfully complete the game on the Hard difficulty setting.
Hard mode
Successfully complete the game to unlock a difficulty option at the main menu. Use it to select the Hard difficulty setting.
Easy money
In the market, there is an orange can. Kick the can behind the counter of the Jet Bakery. A message will appear and say you have received 1,000 Zenny. Leave the room, then return and the can will reappear. Repeat this trick as much as possible to get an unlimited amount of money. Note: Later in the game the amount will be increased to 2,000 Zenny.