I haven't really come across one in all my years of web development, design and consulting.

At some point I worked with a small startup (failed) whose platform was similar in aesthetics to that of craigslist (not used the same way though) and even then I don't think we thought of looking for a 'packaged' solution for this.

I would recommend Wordpress as platform and using a theme as I am sure there are Craigslist inspired themes out there. I would however be careful of certain themes because the majority of our small website clients are owners who feel technically savvy enough to implement a theme but quickly realize that there is more to installing a theme than just 'uploading' it to Wordpress.

Themes should be seen as framing and mechanical systems in a house. You are told you can buy the lot and the structure and relatively easily make it look how you want it but unless you are an experience builder who can put up walls and stucco, install plumbing fixtures and move walls once you find out the current layout didn't work for your items or a window you got is too big and must be re sized... you are better off paying to get it all done for you.

With that said, if you are the learning type and are willing to sacrifice weeks or months to learn to then implement a theme and customize, this is a good opportunity to do so; if not i do invite you to message me and see how I can help you guys out with a website done.

Humberto Valle
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