Hope I was clear on my scenario. Now my questions are:
1. Which home do I list as my Principal Residence in 2020, the condo or new home?
the IRS doesn't ask this question. the address on your return should be the current one
2. Do I need to show 28 days rental for new Home as rental Income, although this Rent was pretty less and not the actual fair market value rent? I wouldn't since this is to defray the interest and other costs you incurred as the owner while the old owner occupied it.
3. For property taxes, mortgage principal and Interest deductions, Depreciation etc. how do I fill this in Turbotax Desktop for Mac
on your old home you prorate the interest 2/3 for old 1/3 for new or use the actual amount you paid during the first 8 months. don't know how your property taxes work. in some places you pay for in 2020 for 2019 which would go on schedule A. in this case you would also prorate the taxes paid for in 2021 for 2020
on the other hand taxes paid in 2020 for 2020 would be prorated
you need to enter the "cost" of the old house for depreciation purposes on schedule E (excluding land costs)
the cost is the lower of your tax basis or FMV on 9/1/2020
your new home works like your old one. again taxes depend on what year your paid or were charged or credited on the closing statement. interest goes on schedule A.
if your average mortgage balance for 2020 wasn't over $750K, all the interest allocated to your residences should be deductible. if not you may want to see the IRS publication 936 to calculate the deductible amount. this limit only applies to your residence nor to rental properties.
