the only recapture on the depreciation is the new depreciation taken from date of death in Nov 2017 to date of sale in 2020.
Nope. You also have to recapture mom's 1/2 of the depreciation taken before dad passed. Dad's half taken before he passed is all that "disappears". Because this wasn't dealt with on the 2017 tax return, the TurboTax program flat out can not deal with the situation correctly, no matter what you do.
Amending prior year's tax return is not an option, because you failed to take (or not take) the proper depreciation for more than two tax years.
In the end, you're gonna do whatever you want, and that's fine. Typically the IRS catches up to this stuff anywhere from 24 to 36 months after the return which shows the sale or other disposition of the property is filed. All I can do is ensure you're well informed, and at this point I've done that. So you might want to consider paying for audit protection for the 2020 tax return. It won't keep you from paying any additional taxes or fines if an audit bears that out. But it will get you representation if/when the IRS catches up to it.
