I have 2 boards - one project based with members and on that is 'private' todo lists with only me as admin / member. Can I invite a member from the other board to be able to view / interact with a specific card on my personal board without them viewing all my other cards? (At the moment I cannot see any invitees in the add member box within the card)
I have just recently tried to do this myself. It does not seem possible. What I did instead (not a complete workaround) was to create a new board in an organization that is visible to the organization members. They can view, vote, and comment, but nothing more.
That would not be possible. Usually by my understanding, at this moment, Trello does not allow you to specify permissions on cards. You can only add members to a card after adding them to the board.
Yep, I've built another board and added the people I want to have access to those cards onto it, then created a Butler rule to mirror cards across boards when I add a label such as
Shared, where it creates a two-way link between the cards.
However, I haven't figured out a way to make the changes two way. meaning If a comment is made on the shared board, it also gets reflected on the personal one.