If the property is your primary residence and not a rental property, payment of maintenance fees does not result in any deductions. Maintenance fees are similar to paying utilities for a single family residence. It is a personal expense and not deductible.
However, if you are billed interest on the co-op mortgage and real estate taxes, those items may be deductible. In Turbotax navigate to Federal Taxes, Deductions & Credits, under Your Home click Start/Update next to "Property Taxes" and enter the other property box of the input screen.
