Do not enter the details of each item, and do not list all 200 items. There is no place for that information on the tax return. Keep the information with your tax records in case the IRS asks about it, but they are not likely to ask. Just enter the totals. When you enter the 1099-K in TurboTax it will lead you through the entries and TurboTax will make the appropriate entries on your tax return.
When you sell personal items at a loss, you do not report the sales on Form 8949.
