The community around buying and selling gear and just watching awesome stuff pop up for sale regularly is one of the reasons I’ve stuck with the site for so long.
Other than FredMiranda, e$ay, Craigslist, I’m not sure what other options there are (I’m not on FB).
Is there any chance something like photomarket could pop up in the fediverse? What other sites are you trading on?
I’ve used MPB to sell a few things last year. Get a quote, ship your stuff in, they verify condition and pay you. It’s easy enough to do.
That said, I have a Nikon J5 and a collection of lenses that I would prefer to sell at a discount as a set where I know, as best one can know, it will go to a good home and see some use.