Hi dutchessk,
It is possible to do that, but it is not a Yada Wiki thing, but a WordPress thing. How easy it is to do and how you would go about it depends on how many pages you want to restrict and the users you want to allow to see them.
For example, here is the manual page that tells about setting the built in visibility of pages:
https://codex.www.ads-software.com/Content_Visibility
If the clients are content authors then you could set the restricted pages to ‘private’ and that might take care of it. Or, if there are just a few restricted pages then maybe password protecting them would do the trick.
Otherwise, it sounds like you might need some kind of membership plugin to better separate the content. I am not familiar with the ins and outs of many membership plugins but I have heard of two:
Justin Tadlock’s Members is pretty straight forward and I’ve used it before for simple things:
https://www.ads-software.com/plugins/members/
Looking at the screenshot it looks like you can define a role for your clients and apply it on individual articles:
https://s.w.org/plugins/members/screenshot-5.png?r=1213014
If you need more control, s2Member free can probably do what you want:
https://www.ads-software.com/plugins/s2member/
I have heard that there are a confusing number of options in setting it up, but it is very flexible. Looking at their FAQs it seems like it would work:
https://s2member.com/kb-article/how-do-i-protect-content-with-s2member/
I hope this information is helpful. Please let me know if I can help further.
