Basically I say the same thing to all Realtors considering WordPress. Joomla although the ideal solution for a brokerage is serious overkill for most people. It is so feature rich that its intimidating to novice or casual site administrators. Because of this 90% of all website conversions we do at UltimateIDX.com are for WordPress.
WordPress is easier to use, easier to learn, and fully capable of being structured as a CMS. A lot of people don't know that you can use WP as a CMS but with some clever template building tricks and a few settings in WP you can build a pretty nice CMS solution with it.
As per different menus on different pages the answer is yes. The easiest way to accomplish this in my opinion is WP Templates!
For instance, I created a site recently where the owner wanted to have a menu specific to "Communities" on his WP Blog so I created a new template titled communities.tpl.php and put this in the header;
<?php
/*
Template Name: COMMUNITIES
*/
?>
The template file would then include a different sidebar I created so instead of <?php get_sidebar(); ?> I use <?php include (TEMPLATEPATH . '/communities.inc.php'); ?> which is a duplicate of sidebar but with a different menu.
My own sites new template has 11 menus in it and each is for a different section of my site, like tutorials or news for instance. I built my newest template to have multiple sidebars and all of which I simply assign by either some clever WP Looping or by template.
Jared Ritchey.