This is what I found for Ohio
https://www.tax.ohio.gov/taxeducatio...our_stuff.aspx
Selling Your Stuff:
Do you have some things you would like to sell for some extra cash? There are many ways to sell your personal items these days; whether it’s through an internet sale, an advertisement in the paper, or a yard sale, they are all considered to be the same type of transaction: a casual sale. Casual sales are not taxable transactions, as sales tax was paid on these items the first time they were purchased.
For example, if you decide to sell your old mp3 player on an online auction/shopping website then you would not need to charge the buyer any sales tax. In this example, you are selling a personal item that you originally purchased for your personal use, therefore you are not required to charge sales tax. This would also be the case if you were selling the mp3 to a friend, at a yard sale, etc. On the other hand, if you purchase an mp3 player at a very low price with plans of reselling it to try and make some extra money, you would need to charge sales tax. In this case, the item was not purchased for your personal use.
There's really no way for eBay to know if you're flipping or selling personal items.