Add Collaborators

The other system I use allows me to invite collaborators into my projects like my subs. This allows them to view pictures and notes about the project them without making them a user in my account. I like the walk through mode but Id have to manually share every single doc every time and there is not unified place for my subs to go and view all notes and pictures related to a project. I use alot of subs so it does not make sense to add them as users to my handoff account. It would be great to have designated space to invite them as collaborators in link a portal format of sorts to better manage sharing information about a job.