How do I categorize the expense of our purchases that we turn around and sell on eBay?

Are you reporting this activity within a self-employment activity and reporting the income and expense on Schedule C Profit and Loss From Business?

If so, the purchases should be reported under as Inventory / Cost of Goods Sold.

In TurboTax Premium Online, follow these steps:

• Down the left side of the screen, click Federal.
• Down the left side of the screen, click Wages & Income.
• Click on the drop down arrow to the right of Self-employment.
• Click to the right of Self-employment income and expenses.
• At the screen Your 2024 self-employed work summary, select Edit.
• At the screen Here's your xxx info. select  Add expenses for this work.
• In the search box in the center of the screen, enter Inventory.
• Check the box to the left of Inventory.  Click Continue.
• At the screen Here's your info for this work, click the pencil to the right of Inventory.
• At the screen Do you have inventory for your work? select Yes, I have inventory to report.  Click Continue.
• Follow the screens to report beginning inventory, ending inventory and cost of goods.