Here are some more recent changes to the Fannie Mae guidelines.
-- Tip income may be used to qualify a borrower for a loan, but the borrowers must prove that they have earned tip income for the past two years and their employers must verify that tip income will continue in the future. The amount of tip income that can be used is the average income over the past two years.
-- The guidelines for 2-unit properties are getting more restrictive. The new down payment requirement is 20% (up from 5%) if one of the units will be a primary residence (the borrower lives in one unit and rents out the other unit), and 25% (up from 15%) if the borrower rents out both units. If the property is a duplex and the borrower is only buying one unit, then the regular 1-unit guidelines still apply.
-- This last guideline change is included here to make you realize that it could always be worse than it is in Colorado. Pity those poor Hawaiian real estate agents :-) "Effective immediately, Fannie Mae will only purchase or securitize mortgage loans secured by properties located on the island of Hawaii that are located within lava zones 3 through 9. Properties in lava zones 1 and 2 are not eligible due to the increased risk of property destruction from lava flows within these areas."