Craigslist has started to add maps to its sales listings, letting people view not just what items are being sold, but where those items are located on a map. Craigslist appears to be starting off with group events — garage sales, yard sales and flea markets — in a move that extends a feature Craigslist first introduced in October for apartment rentals.

As with the apartments move — made just as Craigslist was tightening the legal screws on sites like PadMapper for repurposing its data in their own housing listings — the maps on sale items raises Craigslist’s competitive edge.

In this case, it puts Craigslist into closer feature proximity (pun intended) with startups like Zaarly and Yardsale, which focus on location-based e-commerce from small merchants and sole traders, but also bigger fish like eBay, which also lets buyers view listings based on distance from a specified location.

Focusing first on yard sales makes sense since people seek these out often based on their location. And as with so much else on Craigslist, yard sales have been appropriated by developers who have spotted windows of opportunity to technically innovate in ways that Craigslist has not. Yard Sale Treasure Map, for example, pulls data from Craigslist and offers it in a map view. It’s been running its service since February 2009.

It’s not clear whether and when Craigslist will be extending the mapping feature to other categories like car sales or other, single items listed by individuals, but that seems like an obvious and necessary move:

As with the apartment listings, adding maps to any of Craigslist’s listings makes the site more useful and keeps people transacting there rather than going elsewhere to pick up their data. Craigslist has, in many markets in the U.S. and often elsewhere, become synonymous with certain kinds of sales/rental listings, such as those for apartments, car and, yes, flea markets/yard sales. So any third-party moves to shift eyeballs away from Craigslist to seek out that kind of information elsewhere could, in the long term, impact Craigslist’s pole position.

And nor is it clear whether extending the feature into a new category will signal a fresh wave of cease-and-desist orders from CL against sites that pull its data for their own services.

Also similar to the maps for housing listings: these new maps appear only be getting rolled out in cities in the U.S. and Canada for the time being, but not international sites in countries like the UK and France.

We reached out to Craigslist for comment on this article through multiple channels and will update with any responses we receive.