Lenders use a debt service ratio that weighs your proposed mortgage payment, property tax and heating cost against your gross income, along with any other debt you carry, like a car loan or credit card balance. A first-time buyer with little other debt generally qualifies for more mortgage on the same income than one carrying existing payments.
CMHC, Sagen or Canada Guaranty mortgage insurance applies below 20 percent down and factors into the qualifying calculation too, since the premium is usually added to the loan and increases the monthly payment being tested against your income.
A mortgage broker can run your exact numbers against a Forest Grove price point, and Joel Dyck can connect you with one before you start touring. Get your hand-reviewed valuation from Joel Dyck.