Mortgage interest and property taxes are divided between personal (Schedule A, itemized deductions) and rental use (Schedule E) , proportional to the number of days used for each.

For instance, if you rent out 1/4 of your floor space, deduct 1/4 of your property tax and mortgage interest times days rented /365 as a rental expenses, and 3/4 of the property tax and mortgage interest as a Schedule A, itemized deduction.

So, you will enter a portion of mortgage interest and property taxes in both areas.