gistfile1.ps1

function Get-LAFolderSize {
  Param(
    [Parameter(
      Mandatory = $true,
      ValueFromPipelineByPropertyName = $true,
      ValueFromPipeline = $true
    )]
    [String]$upn
  )
  Begin {
    $resultArray = New-Object System.Collections.Generic.List[Hashtable]
  }
  Process {
    $mboxsize = Get-MailboxStatistics $upn | select-Object -ExpandProperty TotalItemSize
    $reitemsize = (Get-MailboxFolderStatistics $upn -FolderScope RecoverableItems)[0] | select -ExpandProperty FolderandSubfolderSize
    $resultArray.Add(
      [Ordered]@{
        UserPrincipalName = $upn
        RecoverableItemsSize = $reitemsize
        TotalSize = $mboxsize
      }
    )
  }
  End {
    return $resultArray
  }
}