I've seen similar scams on my local Armslist, several times. Some Gomer will post a fairly rare and expensive rifle, for a ridiculously good price. Out of curiosity I'll do a search, and find the exact same rifle, same pics, verbatim description, in another state. But, the rifle had already sold, and for $2K more.
But the info-fishers are especially maddening. They've nearly ruined once great sites. They used to be easy to spot, with their poor grammar and lack of specificity: " I am interested much in your item for sale. If you would please text me, I would purchase it today", or simply asking, "do you still have the item?", but never any further inquiries, and hagggling.
They also almost always use Gmail addresses,too. Me and lots of others around here will post in our adds, that we won;t respond to any messages that even sound like a scammer, so please try to sound like a legitimate local buyer. But a surprising number of people (legitimate buyers) are still too stupid to even do that, so you have to take your best guess on whether to respond. I've never heard back more times than i can recall, it's almost gotten to be the norm.