As Joseph points out, any individual who wishes to buy any item on credit or rent an apartment/business space must be able to provide documentation of income. In absence of a paycheck, tax returns and/or 1099s can suffice. If one does not pay taxes, one would not have these documents and, therefore, would be unable to demonstrate they have an income. As has been pointed out in previous threads on the topic, the cost of massage oil/lotion/cream, lube, laundry services, work space, etc can be tax-deductible.