In this case, if the investor sells the position, he or she will incur a net loss of $750. Another way that an investor can lose large amounts of money as a result of a stock market crash is by buying on margin. In this investment strategy, investors borrow money in order to make a profit.n the simplest sense, investors buy shares at a certain price and can then sell the shares to realize capital gains. However, if the share price drops dramatically, the investor will not realize a gain; in fact, the investor will lose money.