I have a few things to sell but I'm not sure there are any viable alternatives to Ebay other than getting genuinely lowballed at dealers.
I do find the whole thing increasingly bizarre. In the last few months I've bought some expensive things and had no feedback, returned three lenses/cameras for hopelessly misleading descriptions, one of which vendors (all 100% positive feedback) didn't even refund me leaving Ebay to step in. Yet this morning I find that dealer and another of the three have given me exceptional feedback. Weird.
Leica M2, Nikon D700, Bronica RF645, Leica CL, Summicron 40mm, Rolleicord Va, Hasselblad 500 CM Zeiss Planar, Leica 50mm Summicron V3, Hasselblad PME51 metered prism, Zeiss Ikon Super Ikonta 534/16 & Ensign 820 Special - all gone.