I now know that i have to claim my sales from Poshmark, Mercari, etc.. on my taxes next year. I sell these items for less than their original cost and definitely don't mark up items. However, I clearly have met the threshold of $600 and am now wondering if this is even worth it anymore. Most of my items I sell are my family's outgrown items so the date of the original purchases are not necessarily in this current year.  I am super confused and don't want to do things wrong to cause a financial strain on my household when I was just trying to save up money for a family vacation and my daughter's education! 🙂