Ask the agent directly how many secondary-suite purchases they have closed, and whether they know how to pull permit history before you write an offer. A duplex or a permitted secondary suite that shows up clean on the City of Saskatoon's permit records is a fundamentally different purchase than one where the basement unit was finished without a permit.
Financing is the second thing to check. An agent experienced with owner-occupied multi-unit purchases should know which local lenders count projected rental income toward qualifying, and should flag early that CMHC insures an owner-occupied multi-unit property, which changes your minimum down payment math, and should budget a home inspection, typically $400 to $600, that covers both units separately.
The agent's job is to separate a legal income suite from an illegal one before you are financially committed to either. Get your hand-reviewed valuation from Joel Dyck.