Press L1 + R1 + L2 + R2 at the main menu to unlock the cheat menu.
The following codes can now be entered at the cheat menu.
Enter MIDAS at the cheat menu. Begin the game in Get A Life mode,
get into the hot tub with the girl, then press Start to pause game
play. Select "Quit", followed by "Just Quit". This mode unlock all
two-player games, all locked objects, and all locked skins.
Enter FREEALL at the cheat menu. All objects will now cost 0
Party Motel mode:
Enter PARTY M at the cheat menu. The Party Motel two-player game will
now be unlocked under the bonus section in Get A Life mode.
Play The Sims mode:
Enter SIMS at the cheat menu. Play The Sims mode will now be unlocked,
without going through the Get A Life dream house. This is useful for
players without memory cards, who would otherwise need to play through
the Dream House each time.
First person view:
Enter FISH EYE at the cheat menu. Press Circle to toggle between normal
and first person view.