Selling weapons you don't use is not such a bad idea either. Reserved Game Keys F12 - Exit Game. Works everywhere except in game. They give the big cash. Let your opponent do the hard part and make sure you fire the final bullet or set the last explosive.
Invisibility helps a lot.
Perfect if you're hunted. Activate a clone when the other player is trapped in a dead end. Be sure to place them when your opponent doesn't look at your screen and make it credible - leave some other items around it. Turn the light setting on your monitor down low. The game was drawn to look good at my monitor which I always keep at a low light setting.