Your 1099-K income should be included in as self-employment income.

In TurboTax Home and Business or TurboTax Self-Employed

1. Click the Business tab
2. Click Business Income and Expenses
3. Select, I'll choose what I work on
4. Under Business Income and Expenses, select Profit or Loss from Business
5. select yes
6. Answer all the step by step questions
7. Select, Business Income
8. Select General Income
9. You will report your 1099-K income under the question, "Any General Business Income?" 

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