I own a duplex with one part of the property rented out as a condo with q diffenrent address.Should the rental be considered a separate property re % of use by me?

You will report the rental side of the duplex as property separate from your residence. If you have a mortgage on the duplex, you can allocate 50% of the mortgage interest as a deduction for the rental on Schedule E and the remaining amount deducted on your Schedule A, if you itemize your deductions. The same type of allocation between Schedule E and Schedule A can be made for property taxes you pay on the property If there are expenses directly related to the rental you may deduct them in full on Schedule E, including utilities, unless they are not separately metered for the rental unit in which case you'll deduct the portion of utilities attributable to the rental.