It will sell for around $250 and no more than that. For around $500 I can get R5 2600 and RX580 combo brand new which is now more than twice the performance and even if it was not I am getting it brand new.While there aren't many similar used computers to compare it to. Looking at similar used builds which sold. I'd place it around $375 to $425 including shipping.
Sell it locally for cash. You'll lose $100 on eBay fees and shipping if you sell via eBay.