I was looking into using Drupal, or WordPress, as an LMS. A lot of people seem to think that is the way to go.
WordPress is free, of course, but the better plugins cost some money. For example, WatuPro is probably the best exam plugin for WordPress, it costs $87. I also bought access to several plugins from WPMUdev for $100 a year, because WPMUdev seems to have a good subscription management plugin.
I am finding it a little difficult to setup WP for an LMS.