For a timeshare, only mortgage interest and property taxes are deductible.
To be deductible the loan must be secured by the property.
Maintenance and other assessments are not deductible
To report mortgage interest in TurboTax Online
Click My Account (Top right of your screen).
In the pop up window, select Topic Search.
In the search bar, type in mortgage interest
Highlight it and select GO, and follow the prompts.
To deduct property taxes , type in property taxes-real estate.