Once financing is set, build the real cash flow. Take actual or realistic rent, subtract property tax, insurance and a maintenance reserve, then compare what is left against the mortgage payment, keeping in mind the City of Saskatoon must have a permit on file for any secondary suite before its rent counts toward that mortgage at all.
Then confirm the unit is legal. The City of Saskatoon requires a secondary suite to be permitted and inspected, and an unpermitted suite is income a lender will not count and a future buyer's lender may not either, which caps both your financing today and your resale value later.
The number that actually decides the deal is what the building is worth as built, not the listing price. Get your hand-reviewed valuation from Joel Dyck.