The first affordability rule is that your monthly housing costs shouldnt be more than 32% of your gross monthly income.
Housing costs include monthly mortgage principal and interest
Taxes and heating expenses
If applicable, this sum also includes condominium fees
Lenders add up these housing costs to determine what percentage they are of your gross monthly income. This figure is your Gross Debt Service (GDS) ratio.
The second affordability rule is that your entire monthly debt load shouldnt be more than 40% of your gross monthly income.
This includes housing costs and other debts such as car loans and credit card payments
Lenders add up these debts to determine what percentage they are of your gross monthly income. This figure is your Total Debt Service (TDS) ratio.
Based on these ratios, lenders will advise you of the maximum home price they think you can afford.
maximum you can afford to pay in monthly housing costs. Keep in mind that most homebuyers today keep their debt ratios comfortably below the maximums prescribed above. The lower your debt load, the more affordable your home and lifestyle will be.