If they're wanting to add listings to the site, I guess it depends on how complex they plan to have it. I would imagine something with a backend to log into and customizable fields. Don't know anything about Expression Engine (and I think that CMS costs money). WordPress's meta/custom fields can be used to enter form/field items, but it's hardly intuitive unless the client remembers to enter those dropdown fields.

My vote would be with Drupal and it's CCK module as it's very versatile for customization above other CMS's. (In fact, I'm moving a client off of WordPress onto Drupal right now.) However, Drupal has a VERY steep and frustrating learning curve.

Short story? It's gonna cost them. I want a new car that I don't have to pay much for, but it ain't happening either

Awesome. Thanks for the info, Patrick. I'll check out Drupal. I'm going back for a web development degree (just starting) so I'm trying to immerse myself in a few of the more technical (and difficult) sides of the web.

I'd give Expression Engine a second look. I'm just getting into it, and it has been awesome so far. it does cost money for a license, but you get better support and help. I've had all of my questions posted on their forum answered within an hour.

I was over on the Drupal site and a few people were complaining about the speed of the framework once mods are in place. A few recommended ModX instead. Does anyone have experience with this CFS system? I'm reading through the documentation on both. I'll probably end up installing them both and playing around with them before making a decision.

Hmm, I've run Drupal with many modules and never had any major issue with performance problem. D6 is the latest (D7 is around the corner.) Still, whether it's Drupal, Joomla, WordPress or whatnot, modules will always add some overhead to it, even minutely. I guess you can say modules are only as good and efficient as the developers who made them, and two of Drupal's more important and versatile modules (CCK and Views) is champ. (They're actually being rolled into D7's core if I'm not mistaken.)

Like I said though, it depends on your client's needs. If all they want to do is just have WYSIWYG page editing abilities, then Drupal is way overkill. I typically stick with something like WordPress or Joomla for something like that. If they need a lot of custom forms, content types, functionality, etc, then I go with Drupal.

Don't know anything about ModX, sorry.

I'm hosting a test of both Drupal and modX on one of my sites... Gonna play around with them before making any decisions. The clients aren't going to need a TON of options, but the ability to expand as I see fit down the road is always nice.