A grain merchandiser purchases and sells grain as a commodity. Based on the market, which fluctuates based on supply and demand, they decide when to buy grain, then store it or process it until it is an ideal time to sell. They buy from farmers at a basis price at harvest, which is set based on the futures price, or the amount a buyer agrees to pay at a later date. Merchandisers often work for grain elevators, processors, or businesses that can hold the grain until resale. This job agriculture and business knowledge.