That minimum is 5 percent on the first $500,000 of the purchase price and 10 percent on any amount above that, exactly as it would be for a single detached house, provided you are living in one of the units. Buy the same fourplex without occupying it and the math changes completely, since a non-owner-occupied purchase needs a much larger down payment and different insurer treatment.
Rental income from the other units can also help you qualify for the mortgage itself, though a lender only counts a portion of that income rather than all of it when assessing your debt ratios. CMHC's guidelines around GDS and TDS still apply, so run your numbers with a lender before you fall in love with a specific property.
Joel Dyck can point you toward Saskatoon multi-unit listings that fit an owner-occupied purchase like this. Get your hand-reviewed valuation from Joel Dyck.