Wood, M. (1998) indicated the external conditions such as inflation and unemployment or an illness in the family are factors that will determine the amount to be spent to purchase a product and when it is best to purchase a specific commodity. The marketing environment in conjunction with the presence at mass media is an area that in recent decades has gained immense power of influence in today's consumer. For example, usually the ads aim to influence consumer for a particular product of a certain brand, while the factor culture does not "suggest" specific brands but more goods for consumption. For example, one publisher decides to sell a one-use textbook to students.The school makes decision to buy the second hand text book, it's decision will be followed this factor: The second hand book author does not receive any royalties and have no economic interest in the text - when the student buys the text, the publisher can earn less royalty income. It's designed to be a "disposable," one-use text in order to keep the price down. (The used book market actually drives up the price of texts - to see why, think of what would happen to car prices if used car sales were not permitted or think of what would happen to house prices if second hand house sales were not permitted). If the country is facing inflation and unemployment or an illness in the family are factors that will determine the amount to be spent to purchase a product and when it is best to purchase a specific commodity, this bad economic environment factor will influence the coutry's second hand houses and second hand private car sale number decrease, even their prices are less than the normal price 50% or more because many people are losing jobs in the year. In this bad economic environment, how do the used car markets drive up the price of the good? With an used market, the buyer is willing to pay more, knowing that he can resell later. However, without an used market, everyone is forced to buy new cars, raising demand, and thus raising the price of new cars. How to think about these countervailing effects?However, used books and used cars and second hand house markets, they have similar consumer behavioral characteristics. Are the used books and used cars and second hand houses actually have similar consumer behaviors ? However, used car and second hand house markets, they have similar consumer behavioral characteristics. I believe that seond hand book market is different to second hand car or second hand house both market. In used book market, the professor and his publisher have a monopoly on the new textbook, but no one controls the new car market or the new house market. Therefore, if people keep reselling text, the publisher will use their monopoly and raise the price of new books to compensate. In contrast, car manufacturers and house sellers can't do so due to competitive pressure. Imagine that there are two kinds of people, rich and poor, and no market for used books. Rich people are willing to pay more for new textbooks. Poor people cannot afford to buy new textbooks. In the absence of a market for used books, poor people will not buy textbooks. Imagine now that there is market for used books. Poor people are now able and willing to pay second hand textbooks. And rich people now have someone to sell the books too once they are done using these books. A market for second hand textbooks raises the price of textbooks because some people are not able and willing to buy new textbooks but are willing to buy second hand textbooks. In the absence of such a market, they'll spend their income on other goods that they deem more important.