This seems contradictory and/or unlikely: "made substantial improvements to the property during 2022 in anticipation of renting it again (client inherited money and paid off a 2019 reverse mortgage on this property in 2022 as well)"

"The reason for the concern over the reverse mortgage interest is that she inherited a substantial sum of money in 2022 and about 100K of it is taxable."

But you are implying a reverse mortgage was used, similar to real mortgage or HELOC, to improve the property. That narrative and timeline imply otherwise. You don't take out a reverse mortgage in 2019 to improve a property when you didn't inherit money to be able to take any of these actions until 2022.

You seem to be relating two things that are not related, and I like to use the word "discoverable" as in, anyone, including the IRS, can look at the date of the events and the disbursement of the reverse mortgage to see, oh, for instance, did your client live in those payouts in that time period in Nevada where there seemed to be no reason to file income taxes?

Make sure the story makes sense.