If you buy the house as an investment property, you can use his current job to qualify for a loan. Rate's not as good and does require 20% down but it's doable. After one year, you can refinance it as a primary residence. You will have 60 days to pay the mortgage. Do this by closing early in the month and paying interest only at the closing. Waive escrows to soften the monthly payment. So, close July 1. Pay 31 days of interest at closing and first payment due september 1.
Other option is buy it as investment with 30% down using an LLC and I won't ask you to prove income. Rates are single digit. No pre-pay penalty, interest only loan. You must report 2012 as an investment property to the IRS.