Depends on the person doing the labor.
 
 Most will look at scope of project and bid accordingly - more sq ft/less cost per sq ft for same height.
 
 By the hour..least used method. An experienced builder knows approximately how many hours they need - and will bid to factor in their labor cost/needed profit and allow for excess.
 
 Sq foot cost are regional - and will vary based on height as well - obviously a 16’ high building is less difficult than a 32’ high building. Not twice as difficult - but more.