Sims, The Cheats

At the beginning on the main menu press L1 L2 R1 R2 all together to open the cheat menu type freeall then press OK.
Now all objects are free!!!

Cheat menu L1 L2 R1 R2

at main menu screen press R1 R2 L1 L2

Cheat code: MIDAS
Description: Two Player Unlock 
 
  How to use your cheat code: 
     -      At the start
up screen press on R1, R2, L1, L2 at the same time to bring up the
cheat menu.
   -      Type in MIDAS and press
done.
   -      Start up Get A Life mode
   -      Get into the Hot Tub with
the girl
   -      Press Start
   -      Choose Quit
   -      Choose Just Quit
   -      You have unlocked
Two-Player
 

You can unlock objects by doing the following things:

Enter MIDAS at the cheat menu.

Skip work every other day, to the point where they call you but you will not get fired. While you are home, call over some friend(s) and play pool or a cooperative game.

A fast easy way to laydown wallpaper and tile in a big or small room is by pressing and holding L1 or L2 then pressing X this will lay tile or wallpaper in a second instead of using click and drag.

When playing, build a wall ar a fence in a horizontal or vertical position and then put a diagonal fence at the end of the 1st built fence connecting each other. Remove the wall or fence starting from the diagonal fence to earn money..

main menu press L1,R1,L2,P2

to unlock this just enter this at the menu screen