The permit is the whole question. A lender will only count secondary suite income toward your mortgage qualification if the City of Saskatoon has issued a building permit for it, covering egress windows, ceiling height and fire separation, so a beautifully finished but unpermitted suite adds close to nothing on paper even though it looks identical to a legal one. Confirm permit status before you make an offer, not after.
Financing a two-family property still follows the standard residential rules, 5 percent down on the first $500,000 of the price and 10 percent above that, provided you plan to live in one unit, and mortgage default insurance still applies below 20 percent down.
Being a landlord alongside being a first-time buyer adds real responsibility, from tenant selection to maintenance, so weigh that against the financial upside before deciding it is the right first step for you.
Get your hand-reviewed valuation from Joel Dyck.