Sync.. Mirroring -> Behavior Question(s)

Before I start syncing I like to know how the new sync behaves:

What happens if I rename a doc or a folder? Will I end up with the old and the new version in the end (one would come from the laptop, the other (old one) from the server?

Also: I have three databases. Two of which are around 30 GB, the third is around 80 GB in size. I would like to have a synced copy on my server (currently all is on my laptop so I can work with it). Can I simply first copy it all to my server and then start syncing? Or will I end up in a major catastrophe with everything in double?

I also got a MacBook Air with quite a small SSD. Could I have a copy of my Folder-Tree (aka Groups and subgroups) there without all the doc’s and when I scan a document I could have it copyed (or moved) into DevonThinkProOffice ? This way I could have some scan docs for me without having to give her/him full access of all of my database AND that person could work from a complete different location.

thanks for your support
Chris