This is a way to get easy money in Sleeping Dogs.

First, you need to be able to bet in the cockfights. You can't do this from the start.

Once you can, go to the cockfighting place that is on the far left of the map. The key to this place is that it does not have any limits on the bets you can make (unlike the other ones).

Before you place a bet, simply save your game by talking to the NPC you see at the front of the betting arena. Once saved, bet every single dollar you have!

If you win, save your game and bet again. If you lose, reload your saved game and try again.

Keep doing this to get heaps of cash!