So apparently facebook is being used for community sales forums

I was pointed in the direction of one such site on Long Island. Excerpt:

Shopping Hyperlocal, Bub!
Clams, kids’ clothes, and friendly ribbing
By Bridget LeRoy | January 26, 2012 - 12:11pm
First there was eBay — a global community of buyers and sellers exchanging their wares. Then there was Craigslist, which broke the selling down into regions. Instead of buying a tchotchke from Hong Kong or Peoria, a buyer could drive to Medford or Huntington to pick it up. But that wasn’t local enough for some East Enders. Now there’s Bonac Yard Sale — a Facebook page that boasts almost 1,800 members and offers everything from typical yard sale fare like children’s clothing, household items, and electronics to items with a more Bonac flair.
“Fresh local clams,” read a post on Thursday. “Harvested daily from the icy waters of Lake Montauk.” The molluscular morsels are delivered to your door.

Here's the link to the article about the phenomenon

http://www.easthamptonstar.com/?q=News/2012126/Shopping-Hyperlocal-Bub

So I went to facebook and there are indeed many of these yard sale communities. Some are closed groups that require an invitation, others are open.