Limiting what people see and can do in Guide/Help Center

Is there an easy way to limit what people can and can't see/do in Guide / Help Center? The following two use cases are what we're primarily looking to solve:

1. A user has product A and B, but not C. I would like to limit to where they only see content for product A and B.
2. For product A, we only allow 3 individuals to contact Support. We want a way to limit, by user, whether or not they can submit support tickets. We don't want to limit the client organization to only 3 users total though, as they will have far more that we still want them to have access to the rest of the content in the help center, just not support ticket access.

Thanks!
Jake