One sheet per property.
Upper half of the sheet records:
Bought in 2018 ... 2019 2020 2021 2022 .. until 20XX you sold it.
Total Rent (add up all 12 months below)
Jan.
...
Dec
Total Expense (add up all the rows below)
Repair
Interest
Insurance
...
End of Expense
Depreciation Basis
Depreciation (Basis/27.5)
Profit/Loss = Total Rent - Total Expense - Depreciation.
Then you record all your activities in the later half of the sheet.
