Self employed

Thank you, I have no receipts for any of theses items, they were all my childhood collections and my personal items, so how should I obtain these costs as these items typically sell for greater than their purchase price. Last year in turbo tax I left these items blank and claimed all profit and then took fee deductions. This year I was going to do the same and keep my cost as zero, but I was informed that was not allowed. I’m so confused by this and not sure how to get these prices and I don’t want to cause any red flags for this little amount of money. Wondering if I can’t find these costs if I should not use turbo tax and need to file with a cpa. All assistance is really appreciated.