Suppose you take out a 20-year mortgage for a house that costs $482,981. Assume the following:

• The annual interest rate on the mortgage is 4%.
• The bank requires a minimum down payment of 11% at the time of the loan.
• The annual property tax is 2.3% of the cost of the house.
• The annual homeowner's insurance is 0.9% of the cost of the house.
• The monthly PMI is $97
• Your other long-term debts require payments of $715 per month.

If you make the minimum down payment, what is the minimum gross monthly salary you must earn in order to satisfy the 28% rule and the 36% rule simultaneously?