We check that our custom websites and content complies with http://www.w3.org/TR/WCAG and checked with http://achecker.ca/checker
Accessibility checks are built right into the WYSIWYG text editors and validation messages are given when known issues are detected in the site.
Our custom sites comply with WCAG 2.0 AAA. There is no need for alternative "accessible" versions of the custom sites as we do not use or recommend the use of unfriendly technologies such as flash or Java applets.