Documentation of the income also varies depending on the type of income. Hourly wage earners who have the lowest risks usually need to supply paystubs and W-2 statements. However, self-employed, commissioned and those who collect rent are required to provide tax returns (Schedule C, Schedule E and K-1). Retired individuals are required to prove they are eligible for social security and document the receipt of payments, while those who receive income via cash investments must provide statements and determine the continuance of the income from those payments. In short, the underwriter must determine and document that the income and employment is stable enough to pay the mortgage in years to come.