Easy way to make money using stock market:
For every FlyUS corporation, you have an AirEmu corporation. These two stock market options are one of many competitors, and as such, when one falls, the other will rise. This means that if you invest heavily in AirEmu stock, and travel to the airport to destroy nothing but FlyUS airplanes, the value of your stock in AirEmu will raise, and you'll be able to sell it back for more than you purchased it for.
Afraid of the attention you'll receive from the police? Decrease that attention by purchasing a hangar at the airport before the sabotage. Only Michael and Franklin can purchase hangars from the Los Santos International Airport, but doing so will allow you to strut around the airport without gaining any stars, making this sabotage that much easier.
If you're not far enough into the game to purchase a hangar from the Los Santos International Airport, you could always invest in TacoBomb, and destroy nothing but CluckingBell trucks.