IRS has published a Cost Indexes procedure for calculating disaster losses. Based on location & level of damage, you can simply multiply the square footage of the structure by a dollar amount to calculate the loss. Easier than the Fair Market Value calculation, and the calculation is allowed "Safe Harbor" status so that you avoid any hassles with value estimates. However, the instructions for using this procedure say (https://www.irs.gov/forms-pubs/rda-2017-12-14-2018-rev-proc-08:(
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Reporting Requirements on Form 4684 Attach a statement to Form 4684 stating that you used Rev. Proc. 2018-08 to determine the amount of your casualty loss. Include the specific safe harbor method used. When completing Form 4684, do not enter an amount on line 5 or line 6 for each property. Instead, enter the decrease in the FMV determined under the relevant safe harbor method on line 7.
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I can't figure out a way to convince TurboTax to let me do this...
