I believe that the most expensive is Introduction Stage, because the company is launching a new product. Further, the size of market for the product is initially low and thus sales are low. Costs of research and development, testing, and marketing needed to launch the product can be very high. In the Growth Stage is characterized by strong growth in sales and profits. The company can also begin to benefit. This makes it possible for the business to invest more money in promoting their product to maximize the growth stage. In Maturity Stage, the product is established and the aim for the manufacturer is now to maintain the market share they have built up. This is also the time to consider modifications and improvements. And for the Decline Stage, the market of the product will begin to shrink. This could result from a saturated market or because consumers are switching to an alternative. However, companies can still profit by potentially using less expensive methods to produce goods.