A company is considering changing from a cash only policy to a net 30 credit policy. Currently, the company sells 1,000 units per month at a price of $620 per unit. The variable cost is $500 per unit. The company expects to sell 1,200 units per month under the proposed credit policy. The required monthly return is 1%. Assume you were asked to use NPV analysis to decide whether the company should change to the credit policy. What cost of switching amount would you use in your analysis?