Files on a local share?

Ok, So for a long time I have backed up my files to the likes of Google and MS, and then done a separate manual backup to my home file server. This has generally worked well, but it gets tedious, and while it is easy to remember to back up my own files, it is rather a pain to get my wife and kid’s devices to manually back them up.
My thought was to use a tool like OwnCloud as a way to automatically back up files, and then have them available on either a central file share, or a private file share on the home server. The way we have it set now we have a central repository for all of our family ‘public’ documents, and then private shares for personal files (ie, files that we don’t want the kids messing with lol). We are using FreeNAS 11 and the NextCloud 10 which is a built in option. I have had no issues setting things up to automatically import the files to NextCloud… but the moment I point the files to storage outside of the jail I start getting permissions errors.

I suppose the question is 2-fold;

  1. What permissions do I need in order to make this work?
  2. Am I going about this entirely the wrong way, and is there a better way to do this?

The importance of it being in a local file share is that a lot of our files are operational. ie, we take a lot of pictures and videos for projects and how-to videos that we use in other media, rather than simply sharing family pics out to others. We can of course log into NextCloud, download them, and then put them in the project file on the server… but that just seems like so many silly extra steps. They are already living on the server… why should we have to download them to a local device and then re-paste them to a different part of the server? We can do similar things with Pydio, but pydio does not have the automatic upload options we are looking for.