The honest way to estimate it is to build your own number: take realistic monthly rent, subtract property tax, insurance, a maintenance reserve and the mortgage payment if the property is financed, and see what remains against the cash you actually put in. Two buyers on the identical Lakeridge street can get very different returns depending on their down payment and their interest rate alone.
Financing terms move the number more than almost anything else. CMHC's insured minimum down payment, 5 percent on the first $500,000, produces a very different return than a 20 percent down payment on the same property, which is closer to what many lenders expect on a pure investment property, because the mortgage payment and the leverage on your cash are both different even though the rent collected is identical.
If you want a defensible number instead of a rule of thumb, it has to be built from your specific price, your specific financing and a real comparison of what similar Saskatoon rentals actually rent for. Get your hand-reviewed valuation from Joel Dyck.