Andres,
Visibility of the models will depend on the security settings that your hub admin has provided. Projects can be either Open, Closed, or Secret. Open projects are visible to all. Closed projects are visible but can only be accessed by invitation or approved request. Secret projects can only be accessed by receiving and invitation from the admin.
Once you get access in to your project, team members can be either Editors or Viewers. If a consultant is working on a cloud-hosted model, they must be Editors. This allows you to open, edit, or delete models. So, to answer your question, yes, the consultants do have access to your model just like you have access to theirs. In our office, we implemented a team policy that we never open another consultants model. It's really just a professional agreement, but it has worked fine on many projects. The basic rule of thumb is that if the scope of work belongs to somebody else, ask them to edit.
For your first question...
"Are these models the ones that have been only published on the hub or are they the live models that reside in A360? "
When opening through Revit, you will see live models. If you go to the A360 website https://a360.autodesk.com/ you will see the most recent published model. We generally try to publish every few days, so the published copy may be slightly out of date.
Sincerely,
Andy Brack
BIM Manager
