This will monitor the percent free space left on a voluem mounted in folder. We use this on our HP san because for some reason we needed to mount volumes in a folder. This let's us know when we need to add space since we have everything divided by Quarters.
You will need to change the drive letter to the drive you want to monitor and then change the "X" to folder names in this template.
"C:\\folder 1\\folder 2\folder 3"