Instead of amending the prior three years, you should file Form 3115, Application for Change in Accounting Method. You can make the correction all at once on your 2020 tax return. TurboTax does not support Form 3115, so you won't be able to use TurboTax to file if you choose to use Form 3115. I recommend you find a local tax professional to help with the situation.
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Thanks but my real question; is the date supposed to be 05/01/2014 or 01/01/2017 in that bucket?
Also is Nonresidential real property correct?
