Cost per square foot is a benchmark, not a bid. It becomes meaningful only when numerator, denominator, scope, and context are defined the same way.
Define the formula
Divide a clearly defined project cost by a clearly defined area. Write both definitions beside the result so another person can reproduce it.
Normalize before comparison
Adjust or segment benchmarks for location, time, project type, size, height, site work, occupied conditions, quality, and exclusions. Averages without those controls can mislead.
Move to assemblies and quantities
Use square-foot benchmarks for feasibility and reasonableness checks. Develop the bid from measured quantities, assemblies, subcontractor input, labor, risk, overhead, and profit.