I have found several resources that use the following script to get folder sizes
$colItems = (Get-ChildItem $startFolder -recurse | Where-Object {$_.PSIsContaine
This is similar to https://stackoverflow.com/users/3396598/kohlbrr answer, but I was trying to get the total size of a single folder and found that the script doesn't count the files in the Root of the folder you are searching. This worked for me.
$startFolder = "C:\Users";
$totalSize = 0;
$colItems = Get-ChildItem $startFolder
foreach ($i in $colItems)
{
$subFolderItems = Get-ChildItem $i.FullName -recurse -force | Where-Object {$_.PSIsContainer -eq $false} | Measure-Object -property Length -sum | Select-Object Sum
$totalSize = $totalSize + $subFolderItems.sum / 1MB
}
$startFolder + " | " + "{0:N2}" -f ($totalSize) + " MB"