On the SQL server I only have PS1

and the hard way gives me error:

Unexpected token 'in' in expression or statement.

At D:\Temp\freeInDB.ps1:11 char:40

+ $cmdStatement+=foreach ($DFileGroups in <<<< $db.FileGroups)

I just need to know how much unused space (GB) I have in 309GB database.

even a SQL script will do.