You and four friends have decided to create a new service company called Unpacking for You. Your company unpacks for families once they have moved into a new house. Your business is primarily a cash business. Each family will pay you $100 for each room that is unpacked on the same day you finish the service. How will your business make sure that the payment from the customer is valid? How will you ensure that you will receive the cash when the customer pays the employee in cash?