I rent out part of my home and when I input the rental expenses information I told TurboTax to do the apportionment calculation based on the rental unit being 20% of my home. For the mortgage interest, TT asked me only for the full amount of the mortgage interest reported to me on Form 1098. I had 2 Form 1098 because I refinanced in 2021. I entered the combined amount in my rental expenses and TT told me that it was doing the apportionment for my personal deduction. However, when I went to do the Deductions and Credits section of my return, it asked me to enter information from my 1098s. This included information not just just about the amount of mortgage interest reported but about the loan origination date, the principal amount, etc. None of this information was requested at the time I entered my mortgage interest information in the Rental income section, so I assume this was all important information being collected. HOWEVER, once I completed my return I saw that TT appeared to have added the amount of mortgage interest TWICE - the apportioned section calculated under Rental expenses as well as the amount it asked me to enter under Deductions. This is clearly an error. So I deleted all the mortgage interest information I entered under Deductions. But how is that information (loan origination date, principal, etc.) supposed to now be captured??? BTW, I looked back at my 2020 return and see that TT erroneously calculated my mortgage interest deduction based on exactly the issue I just experienced with the 2021 program.
