Grand Theft Auto 5 offers several tips and cheats to make your life easier.
This list references the key combinations and their associated bonuses for GTA 5. The key combinations is different for each consoles (Xbox 360 or Playstation 3), but the results are the same. Besides the regular cheat codes, there is another way to make easy money in GTA 5. You can repeat the mission where you need recover an underwater case (containing 12000 dollars), each time with a new character.
The complete list of these manipulations is very easily on the internet.