Classified program like Craigslist?

[ownthisdomainnow]

Can anyone give me direction? I am looking or the best pre-made program for starting a system like you find on Craigslist, or something similar.

I want people to be able to sign in and place ads with ease. I want to be able to manage it with ease. And I want to be able to have banner ads placed with ease? I would like for it to incorporate video as well. (Video ads)

I am not needing to find something free, unless free is the best. I want to be able to plug it up and go.

Thanks