I'm guessing the answer is "no", but thought I'd ask for advice here regardless.
I don't have FB. Haven't for years. I ditched it long before I started giving a shit about Privacy, it's just so toxic and silly.
That said, I'm a retro gamer constantly on the hunt for holes in my NES/SNES collection and unfortunately the folks in my area seem to be quite a bit more active on FB Marketplace than Craiglist, Offerup, or Nextdoor For Sale pages. In the past I've asked my spouse to message the seller for me and then show up with cash and buy what they're selling. Increasingly, sellers are scared of scams and seem to be less responsive to this type of inquiry.
Is there anyway to minimize footprint in FB? Or perhaps a way to use Messenger without an account? You can browse the marketplace pages of your community without an account, but they'll pester you the whole time and you can't save your locale without signing in.
Or am I out of luck entirely? I thought about posting "In Search Of" type posts on Craiglists to bring the buyers to me, but my area has several of those already and I'm not after bulk lots or other platforms other than the old Nintendo stuff.
I do check Ebay as well and have found a few gems for decent prices and a local shop occasionally has some stuff that hasn't been completely picked over, or i show up right after someone sells their collection and that's rad, but that's rare.
I’d suggest a simpler setup of Firefox, uBlock Origin, and a container extension to keep Facebook isolated from your regular browsing. Facebook Fences is a decent one, which also blocks the “Share on Facebook” buttons (which have embedded trackers) on sites.
Unfortunately if you want to use the marketplace, you will need to make an account. Some people have suggested a fake account, and there may be some merit to that. But in reality, Facebook does so much tracking across the web that they’ll already have a phantom account for you. Basically, they track traffic across the web (with their various share buttons, like counters, etc,) and will build a phantom account for you based on your browsing habits.
Then when you make your account, (regardless of whether or not it’s a real name or email,) they’ll simply link that phantom account to your created account. So even when you first make an account, they already have a really good idea of who you are based on your traffic patterns. Hell, they probably even know right away that it’s a fake account.
Using a privacy oriented browser is great, but it ironically makes you easy to fingerprint when signing into accounts, because very few people are cruising around the web with librewolf as their daily driver.