I am seeing a lot of Form 1099-K's this year for clients that have sold personal items at a loss. I've received conflicting direction on whether these transactions need to be reported on Schedule D or not. I understand you cannot take a loss against other income for personal items sold. What do I do about a client who says they only sold a few personal things, but I can see from the 1099-K that the number of transactions was over 700? It looks to me like maybe they are going around to yard sales and buying items then selling them for more of a profit. If I don't include the 1099-K information on the return, will the return be flagged by the IRS for missing information on the 1099-K? Thanks!