On commercial property, can depreciation be taken off the value needed to be covered by flood insurance to get actual cost?

I don't understand your question as presented. But Actual Cost Value = Replacement Cost Value minus Depreciation.

Coverage for non-dwelling properties (and even some dwellings) won't pay above Actual Cost Value (ACV). As Randy defined above, ACV is the Replacement Cost Value (RCV) less physical depreciation.

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