A lender

An A lender wants a clean file: a credit score around 680+, provable income (T4s, notices of assessment, or two years of self-employed history), and a property in marketable condition. In exchange you get the sharpest rates in the market and the lowest borrowing cost over the life of the mortgage.

If your file has a wrinkle — bruised credit, recently self-employed, unusual property, or debt ratios just over the line — an A lender will usually decline rather than price for the risk. That's not the end of the road; it's the signal to look at a B lender or private financing with a plan to graduate back to A pricing.

Because every A lender weighs the same file differently, the value of a broker is shopping it across all of them at once instead of taking a single bank's answer as final.