Joe is self-employed in a store that has a rental value of $500 a month which he pays, but he can vacate the building without giving notice. His other expenses are $100 a month for maintenance. He makes $25,000 a year on net sales (total revenue minus the wholesale cost of the product). If he quit his job and worked the same number of hours elsewhere at a job he liked equally well, he estimates that he could make $20,000 a year. No one else can be hired to work in the store. Suppose that Joe had a long term lease which requires him to pay the rent even if he doesn't operate the store. What should Joe do