Lenders scrutinize the rental side more closely than they do an owner-occupied purchase. A signed lease, proof of a permitted suite and a history of collected rent all strengthen an application, while an unpermitted unit's income usually cannot be counted at all.
Sold comparables from Saskatchewan REALTORS Association listing data set the purchase price ceiling, and a lender will order its own appraisal rather than accept a listing price at face value, particularly on a property being bought partly on projected rent.
The financing math only works if the property's real condition and legal status hold up, which is exactly what a desktop estimate cannot check. Get your hand-reviewed valuation from Joel Dyck.