The cost of a quonset can be a bit of a loaded question so we always recommend speaking with a building consultant, and it's the reason each building must be quoted individually. The price per square foot of a quonset decreases the larger the building is. They can start as low as $5 per square foot, however, you then have other considerations such as: customizations like windows and doors load requirements such as snow and wind loads which can require thicker steel local building code requirements whether the panels are painted or not shipping costs (a significant factor for a steel building) the foundation style chosen and requirements additional elements such as wiring, plumbing, foundation baseplates, etc. We recommend requesting a quote here and finding a supplier who can provide the best price for your steel building.