You may try the free "miniblog - message board" from http://webprosonly.com: it is MUCH easier to set-up than Wordpress! (php scripts tag)

You can achieve this by using WordPress and some plugins, or using other CMS software like Joomla or Droopal.

Probably what's more suited is a community message forum program like SMF (Simple Machines Forum) and PHPBB, Vbulletin or IP Board. For example, you can literally have an up and running SMF message board in 30 minutes or less.

And once your message forum software is installed, simply setup your categories and from there you're open for business. Plugins will help you to display your listings nicely, plus give control to you over spammers and making it easy to upload a photo and add a listing too.

Good Luck!