The measurement itself is not standard either. Some quoted figures include developed basement area and some do not, some measure exterior walls and some interior, and a bungalow and a two storey home of identical total area produce very different rates because the bungalow carries a larger foundation and roof for the same living space. Multiplying by a single number silently assumes all of that away.
Land is the part the arithmetic ignores completely. Two houses of the same size on the same street can be far apart in value because one sits on a wide lot with lane access and redevelopment potential and the other does not. Where zoning permits an infill, the land can be worth more than the structure standing on it, and a rate per square foot cannot express that at all.
Use the figures that are actually published instead. Saskatoon's benchmark price was $444,700 in the latest association report, up 2.8 percent year over year, with 446 sales and 1.63 months of supply. Then price your specific property from real sold comparables, which is what Joel Dyck's hand-reviewed valuation does.