Export multiple variables to csv

Question

I am a bit lost in adding my results to a csv.
I tried several way, but the objects are not written to csv.
# Var
$wdb = Read-Host "Enter Mailbox Database"
add-pssnapin microsoft.exchange.management.powershell.e2010
Import-Module ActiveDirectory
$ADSettings = Get-adserversettings
If ($AdSettings.ViewEntireForest -ne $true) {
Set-AdServerSettings -ViewEntireForest $true
function Get-ADUserLastLogon([string]$userName)
$dcs = Get-ADDomainController -Filter {Name -like "*"}
$time = 0
foreach($dc in $dcs)
$hostname = $dc.HostName
$user = Get-ADUser $userName | Get-ADObject -Properties lastLogon
if($user.LastLogon -gt $time)
$time = $user.LastLogon
$dt = [DateTime]::FromFileTime($time)
$AdvStats = Get-mailbox $U.SamAccountName | Get-MailboxStatistics
Write-Host "$($username) last logged on at: $($dt), the Mailbox was last accessed on $($AdvStats.LastLogOffTime) by $($AdvStats.LastLoggedOnUserAccount).
The mailboxsize is $($Advstats.TotalItemSize) and contains $($AdvStats.ItemCount)."
$Item = {
$Item.UserName = $userName
$Item.LastLogonAD = $dt
$Item.LastMailboxLogoff = $AdvStats.LastLogOffTime
$Item.LastLoggedOnMailbox = $AdvStats.LastLoggedOnUserAccount
$Item.MailboxTotalItemsize = $Advstats.TotalItemSize
$Item.MailboxItemCount = $AdvStats.ItemCount
$Collection = $Item.toString()
$DisAcc = Get-Mailbox -database $wdb -resultsize Unlimited | ? {$_.Identity -like "*/Disabled_Accounts/*"}
Foreach ($U in $DisAcc) {Get-AdUserLastLogon $U.SamAccountName}
$Collection | Export-Csv -Path C:\Temp\DisabledAcc_$($wdb).csv
# End
I also tried with select-Object ... | Export-csv -Path ... -append
Answers provided are coming from personal experience, and come with no warranty of success. I as everybody else do make mistakes.

Answer 1

Thanks for your reply, it is greatly appriciated. I am not a native scripter, but am working on automating more via powershell and get some more decent experience on the subject. 
The idea of the script is to get the last logon to AD for users in a Exchange database, in addition it shows the last logon to the mailbox and the user who logged on last to that mailbox. As aditional information I also added the Mailbox size and Item Count. 
The script i created runs in which it displays the requested information.
Write-Host "$($username) last logged on at: $($dt), the Mailbox was last accessed on $($AdvStats.LastLogOffTime) by $($AdvStats.LastLoggedOnUserAccount).
The mailboxsize is $($Advstats.TotalItemSize) and contains $($AdvStats.ItemCount)."
In addition i wanted to export that information to a csv, which i can again use for information and maybe even further in the eventual cleaning process. However that is failing. 
The scriptlet you created only looks at lastlogon to the mailbox and not on the AD object. It could be that the account is still used, while the mailbox is not, therefore I want to collect all that information.
Answers provided are coming from personal experience, and come with no warranty of success. I as everybody else do make mistakes.
Nope
Actually, i retreive information from ADuser 
$user = get-aduser $mbx.name
-properties enabled,lastlogondate
You can simply add lines for get-mailboxfolderstatistics
$user = get-aduser $mbx.name
-properties enabled,lastlogondate
$mbxstat = get-mailboxfolderstatistics $mbx |select itemsinfolder ... whatever you want
Then add rows to the table
Itemsinfolder = $mbxstat.itemsinfolder
Got the idea?    You can combine any cmdlets and put them into one table
At this moment im kinda busy doing my work, but later i can modify my script to get exact output you need.
In your script, your primary source of data is AD user, i use maibox instead and get the Aduser info from there
Modified my script (few lines above) .. it should work for you  (i would run it over all mailboxes though: get-mailbox -resultsize unlimited)