This is a basic helpful script. I just added comma formatting to make it easier to read. Thank you.
SELECT
Name
, Filename
, convert(varchar, cast(convert(decimal(12,2),round(size/128.000,2)) as money), 1) as FileSizeMB
, convert(varchar, cast(convert(decimal(12,2),round(fileproperty(name,'SpaceUsed')/128.000,2)) as money), 1) as SpaceUsedMB
, convert(varchar, cast(convert(decimal(12,2),round((size-fileproperty(name,'SpaceUsed'))/128.000,2)) as money), 1) as FreeSpaceMB
FROM
dbo.sysfiles