How much did you pay to originally build the house?
You mean how much did @chuckjim pay to build the original house, right? The house that was destroyed by the fire? That would be the cost basis and the basis for depreciation. The $450,000 received from the insurance company is a nonrecognition event so no tax would be due on the difference between the $450,000 payout and the basis of the house that was destroyed by fire.
