Are they a “sub” crew? As in you pay them X dollars per sq and they have their own insurance and are a legit separate intity from your company? If so, it’s not payroll for starters.
If you actually measured the house, and know what it should take basecon a reasonable waste factor, there should be no reason for overages that amount to anything appreciable. If this crew is consistently short on material, they are thiefs, and shouldn’t be used. If your using eagle view, sky measure or any other program for the lazy, then you really don’t know because they only say they are accurate to within what 7%?
Get a good tape measure and use it!