The reason why most brokers, landlords, and veteran office searchers prefer $/sqft rather than $total is that $/sqft allows for easier comparison of price efficiency between spaces of different sizes. Using $/sqft is also preferable when the total size is fungible e.g., when a space can be subdivided or combined.

Several of our A/B tests have used total size but it doesn't have a big enough effect on conversion to be measurable.