Fortunately, my area has a popular classifieds section at a local newspaper website that everyone seems to have standardized on. I guess people probably also use Facebook, but the local classifieds has a ton of listings.
So if Craigslist is essentially dead in your area, check the classifieds in whatever newspapers are popular in your area, maybe there’s another relatively popular option. And regardless of what you do, it’s totally fine to make posts in multiple places, so make a Craigslist post and updated it alongside whatever one you end up using.