For a long position on a standard equity, the exposure is both the amount of money that it cost to open the position, and the maximum amount of money that could be lost from the position (if the stock loses all of its value).

For short or leveraged positions, the risk/exposure may be theoretically infinite or may not correspond to the cost to open a position. In any case, this property returns a value that corresponds to the cost to open the position.

Note that this value does not include commissions.