Someone who owns a townhouse wrote to a real estate advice columnist to ask whether he should sell his townhouse or wait and sell it in the future when he hoped that prices would be higher. The columnist replied: "Ask yourself: Would you buy this townhouse today as an investment? Because every day you don't sell it, you're buying it." Do you agree with the columnist? In what sense are you buying something if you don't sell it? Should the owner's decision about whether to sell depend on what price he originally paid for the townhouse?