Can I (and where) deduct expenses like sheet, towels, and other items that are exclusively for rental portions of my home?

Here is a helpful TurboTax FAQ with the steps to enter rental income and expenses.  If you have already entered income, when you get to the Rental and Royalty Summary screen, select Edit next to your rental to add expenses.  This will bring you to another screen and you will see a categories named Expenses and Vehicle Expenses.

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