Mac Pro memory issue
MacBook Pro (Retina, 13-inch, Late 2013), iOS 7.1, Mail
That is why I hate suggesting Terminal commands. One extra or omitted space can destroy your entire system. In this case, the tmutil command is not that dangerous. Try it again with a space before the /.
Make sure he Trash bin of Photos (!!) and the mac itself is empty.
Then open SystemPreferences->Spotlight->Privacy:
add all disks that are connected in the Privacy window, including the startupdisk, then wait 10 seconds, then remove the Startup disk from the Privacy window, again.
Restart. Spotlight will start reindexing, so uses a little bit of system power.
Then look in the Finder window how much free space you have. All these other things via AboutMyMac are no good for seeing free space or difficult to interprete.
Mac Pro memory issue