Note: As of 2017, you can no longer use a income based repayment plan if you apply for a USDA or FHA loan. You will have to be on a fixed amount that does not change year to year. The processing of this can take up to 2 months to be finalized so start this at least 2 months before applying for loan.
To apply for a home loan you cannot be in default and you will be required to be on a payment plan with the IRS. You can set up payment plans by visiting the IRS Payment Plans Website.