To enter the following cheats go to your pda screen and switch to the factions screen (on your pda) to type the codes(use the d-pad)the codes will not work after a loading screen unless you re-enter it
INVINCIABLITY(IN WATER TOO)
press: up,down,up,down,left,right,left,right(when you go into a vehcle or coppter it can,t blow up unless you get out of it)you should hear a noise when it activates
ALL SHOP ITEMS
press: down, down, down, down, up, left, right, right
LOTS OF MONEY
press: right, left, right, right, left, right, left, left
INFINITE AMMO
press: right, left, right, right, left, right, left, left