Marketplace. It's horrible, but the area I live in has mostly abandoned craigslist and if you want to buy/sell used stuff, marketplace is where you have to be.
I recently perused Marketplace, and it appears to be so thoroughly infested with barely disguised scams, bogus prices and other garbage as to be usable by only the most intrepid and determined shoppers.
I feel like Craigslist squandered its effective monopoly with online classifieds.
While I do not think that the company needed to modernize the site’s UI, it baffles me that their anti-spam tools are so rudimentary. Most searches yield irrelevant keyword-bombed results, and, such results tend to be nearly identical listings.
I had yearned for a viable Craigslist alternative for years. Sadly, Facebook Marketplace won. I don’t feel comfortable searching for anything due to the fact that Facebook will inevitably use my queries to further profile me.