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I have finished the main story and all my main characters ended up making close to 31 Million apiece from the Big one. I only finished one Assassination mission so far which was the Hotel assassination, but i didn't play others because people advised me to reserve the Assassination missions to the end of the game.
This is all i know currently that these assassination missions end up killing some company's CEO and trick is to invest on their opposite number.
I want to know what others used to make money from these missions like if i should invest all my money on opposite company's stock from all the characters and play the mission and another question being once i complete the mission when is a good time to sell the stocks again?