I've been looking for a bluray player for my new LG OLED TV and found this open box Sony BDP-BX650 bluray player with 4k upscaling, 3D, streaming, WiFi for $36 after coupon (PCOLUMBUS2017) on eBay -
Sony BDP-BX650 [ebay.com]
The BDP-BX650 is the Costco version of the BDP-S6500. I'm guessing these are store returns to Costco that have been checked and are being sold again.
Please note that this is NOT
a 4k bluray player - it only upscales/upconverts the picture to 4k.
Current price for a new BDP-S6500 on Amazon is $88.