What is the minimum income for a borrower looking to purchase a $400,000 home with a $320,000 mortgage based on a back-end ratio maximum of 36%? The mortgage has a rate of 6% and a term of 30 years. The borrower has $1,000/month in school loans and makes a car payment of $850/month. The property taxes on the property are $4,000/year, the hazard insurance premium is $800/year, and there are no association dues.