A really nice thing to consider is using wordpress to blog your classified listings. The aim is to use one of the best types of web sites (SEO wise) to drive traffic to your classifieds site. The blog sucks the new listings over every night automatically. Once set up there is nothing to do. My intention is simply to capture visitors and redirect them as painlessly as possible. property for sale france I am willing to offer this as a solution on a hosted basis (managed service) only as it contains quite a lot of development work and quite a few 'trade secrets' which have been learnt over a long period of time in terms of search engines.
Using RSS to syndicate content is an amazing tool. David has a great example above. Another great way to use the RSS feed is to auto-post classified listings to such services as Twitter, Facebook, Feedburner etc.