BRUNSWICK — Imagine an online marketplace like Craigslist, except you can see every seller’s real name and nearly everyone is practically a neighbor.

And that person selling the playground set? Turns out she’s a friend of a friend.

Welcome to the “Brunswick, Maine Area Online Yard Sale,” a Facebook group that has become a go-to destination for nearly 1,500 people to sell and trade goods.

In the past few days alone, dozens of users have posted items for sale, including video games, children’s clothing and furniture.

Similar Facebook groups have emerged in Topsham and Yarmouth.

One classifieds industry expert said the groups are part of a larger trend of emerging online marketplaces that place a greater emphasis on identity verification and local communities.

But unlike other online marketplaces, the Facebook groups are started by one person using one of the social network’s features: the ability to create customized news feeds where members can post messages and images.

More notably, the Brunswick Facebook group is gated: Prospective users must first request access or receive an invitation from an existing member.

Jill Ellis, founder of the group and a Brunswick resident, said the virtual gate exists in an attempt to keep sales within the greater Brunswick area.

It also helps her weed out spam.

“Whether it’s the normal spam or just someone from away who likes to peruse yard sale sites for their business,” Ellis said, “we try to keep it as local as possible, so there is that comfort level.’

The vetting process may be safer than anonymous marketplaces like Craigslist, she said, but it isn’t perfect.

That’s why Ellis adopted a set of rules to encourage users to be careful. The rules came from a similar Facebook group in Pennsylvania that inspired her to start the group in the first place.

“If you know someone who knows (the buyer or seller), you can check ahead,” Ellis said. “That’s in the guidelines: don’t put out your phone number or address, and if you don’t know them, meet them in a public place. Shop safe, basically.”

She said one easy way to vet people is by looking to see if a user has any mutual friends listed on their Facebook profile.

“The side benefit for me is I’ve found neighborhoods I’ve never known before and met people I’ve never met before,” Ellis said.  “That’s been the benefit: meeting people and discovering Brunswick.”

Kate Kalajainen, another Brunswick resident and a friend of Ellis, said she was invited to the group when it only had a couple hundred members earlier this year.

Having sold and bought a handful of items through the market, she said she likes the group because it keeps sales in the area and it has saved her some money.

“If my child has outgrown her ice skates and your child needs ice skates, we can make an exchange,” Kalajainen said. “Here, if you find something, it’s likely to be something like 15 minutes away.”

Peter M. Zollman, a classifieds industry expert at AIM Group in Altamonte Springs, Fla., said do-it-yourself Facebook marketplace groups are a “relatively recent phenomenon.”

The groups, which he estimates number in the thousands, have emerged alongside new social networks and services that also place an emphasis on local communities.

Some of those services include Nextdoor.com, a private social network for neighborhoods; Rumgr.com(pronounced rummager), an online garage sale network; and Copious, an iPhone app focused on trading goods with friends.

Zollman said the built-in social network of Facebook groups allows users to more easily vet each other before meeting in person. It can be a safer way of doing business online, he said, than using an anonymous service like Craigslist, “which can be the Wild West at times.”

“You should be equally cautious when you use a Facebook group or meet-up group,” Zollman said, “but the likelihood of it being someone who is from nearby and is known to friends, relatives or peers is much greater.”

Dylan Martin can be reached at 781-3661 ext. 100 or dmartin@theforecaster.net. Follow him on Twitter: @DylanLJMartin.