The cost of inventory includes the cost of purchased merchandise, less discounts that are taken, plus any duties and transportation costs paid by the purchaser. If the merchandise must be assembled or otherwise prepared for sale, then the cost of getting the product ready for sale is considered part of the cost of inventory. Technically, inventory costs include warehousing and insurance expenses associated with storing unsold merchandise. However, the cost of tracking this information often outweighs the benefits of allocating these costs to each unit of inventory, so many companies simply apply these costs directly to the cost of goods sold as the expenses are incurred.