Yes, you may report maintenance fees as Investment Expenses on Schedule A (Itemized Deductions).
The easiest way to find this section of TurboTax is to open your return and use the Search box at the top right side of the TurboTax header. Click on the magnifying glass, type in "investment expenses", hit Enter, and click on "jump to investment expenses" to go directly to beginning of this topic.
Or go to Tools >> Topic Search. Type in "investment expenses", then click the topic in the list to go directly to the start of this section.
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Investment expenses are a miscellaneous itemized deduction. This means they are deductible only if and to the extent they, along with your other miscellaneous deductions (if any), exceed 2% of your adjusted gross income.