Revisiting this topic with new info.
Maryland has now joined the threshold of $600 Paypal goods & services payments regardless of the number of transactions and Paypal will be sending a 1099 for 2021 sales.
I also saw on another media outlet that Paypal (and eBay, etc....) will start doing the $600 threshold for all states starting with 2022 good & services sales. This change to $600 from $20K & 200+ transactions was part of the new stimulus bill.
Even if you kept buy and sell records the issue becomes correlating the actual profit (taxable income) you made vs. the 1099 reported to IRS (state, local and federal). Other than filing a Schedule C (profit and loss for business) I see no way to document losses otherwise. I am having my accountant look into any ways to legitimately do this as I really enjoy my catch and sometimes release hobby of buying knives and vintage cameras, many of which get moved on after short trial period, usually at break even or a loss.
This same issue will apply no matter what you sell....downsizing your houshold, thinning out old sports equipment, electronics, etc... all stuff you already spent taxed income on, now becomes taxable as if you are a business buying just to sell unless you can document and file profit and loss (like a business).