If the two floors are truly separate from one another but
similar in size, then you could consider the rental floor and your residential
floor as two separate properties.
Enter the information in the rental income and expenses
section for the rental portion as if it is a property on its own. The main thing to consider would be to only
enter half of the cost of the property for depreciation, enter half of the
property taxes, enter half of the mortgage interest, etc. for any items that
are paid for the whole building.
Use the same idea when entering information for your home
office that is included as part of your residence portion of the building.
