Oh, man. If you figure that one out, let me know. I'm in the same boat there.
Steve
If you intend to fully self host something, the full mediawiki software that runs the back end of wikipedia is suitable. It’s entirely composed of BSD/GPL/Apache licensed software. If you have any persons who are competent at administering and customizing stuff on normal LAMP stack servers it should be easy to install and understand. The VisualEditor extension is the same WYSIWYG GUI for editing in browser as is used on full wikipedia today. For an example go to any public wikipedia page and hit ‘edit’, make some changes but don’t save them.
https://www.google.com/search?client=ubuntu&channel=fs&q=mediawiki+visualeditor&ie=utf-8&oe=utf-8