The tangerine market is the single most powerful tool in this game. At any point in the game progression you can use it to guaranteed double or even triple your current money if you are patient. the best way to play the stock market is to buy a stock when the stock hits the mid 20s and wait. When that starts to make a profit anywhere within the 30-40 range sell them and immediately buy another stock in the 20s this maximizes the profit because those stocks will almost always start to increase. Bouncing from stock to stock like that can make getting all the speed achievements really simple and make insane profit in a short time.
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