I've been using an app called JDisk report which pinpoints the biggest space hogs on my drive. I've been trying to run it on the family iMac but the results are quite inaccurate because the only thing my user account has permission to access (and therefore the only thing it can scan) is my user folder, shared folders and public folders. I tried using the chmod command which I though would change the permissions of the folder to which it was executed on and all folders within, but it only does it per-folder, which makes the process extremely tedious. There must be a better way to do this.
If it helps, I'm running macOS 10.13.6 High Sierra on a mid-2011 iMac (base 500GB model except the RAM has been buffed to 12GB)
/Users/YOURUSERthe potential risk is small, but you shouldn‘t have access issues there anyway. In any case I would make sure to have a recent backup before trying anything fancy. – nohillside Aug 10 '19 at 12:16