Is this Website a scam?

[Average John]

http://www.classifieds-local.com
I've had some bad luck trying to sell my mustang on craigslist and some random number sent me a link to this website, is it a scam or is it really legitimate?
They charge a "one time payment of $21" to post an ad
He sent me this message
"Hello, saw your car listing , many buyers in your area are looking for your car type at your price. go to http://www.SmartListings.net"
It was from (804) 632 - 4320

[Emmy]

Absolute scam and bullshit, There are barely anybody selling or buying off of that website, its just a ripoff, keep using Craigslist its free.

[Kittysue]

If you can't sell your car for free on Craigslist, why do you think you'll sell it on a lesser known site by paying to list it??

Here is the Alexa rating for that site http://www.alexa.com/siteinfo/smartlistings.net#
Here is the Alexa rating for Craigslist http://www.alexa.com/siteinfo/craigslist.org
So would you rather post on a site that doesn't even appear in the top million websites in terms of traffic or one that ranks 8 in the US?

I don't know if the site is legit or not - it may be but it doesn't come anywhere near the traffic of Craigslist