Oh Joy.....
Yes I'm a Facebook user, mostly family stuff, and will state with no hesitation that it's about the most irritating jumble of bad design, bad functionality, and generally offensive policies that I've ever seen from a major corporation.
They literally do nothing well, including sell advertising.
In fact, one of the reasons why I finally installed an ad-blocker in my browser is because I was SO tired of Facebook's endless stream of ads for things that I have utterly no interest in, from companies that I would never, ever do business with.
This is bound to be a disaster. I can see no way that Facebook could do this without balling up the whole works.
God only knows WHAT their gobsmackingly bad algorithms will do with an endless stream of used furniture ads.
And honestly, given the ease and ubiquity of Craigslist I can't see why anyone would bother with Facebook to sell their used crap.