Email notify users of new or modified listing

[abkeller]

I've seen a few posts on this issue, and some requests for this functionality, but no resolution. I think I've got it narrowed down to which lines of code need to be modified, but am not certain of the syntax/command to make it work.

I want all users who submit a new ad, or modify an existing ad, to receive the confirmation email with the link to their ad detail page once they've completed the process. As the software is built, only the administrator receives these notifications, which doesn't make sense. I don't care if someone has posted, much less modified an ad, but I'll bet my users/sellers would like to get this auto notification.

I've been trying to pin down where exactly in the code I need to make what should be a simple change to change the email-to FROM the default admin email TO the user email.

I found this line in the usermodifylistings.php;

$mail->AddAddress(ADMIN_EMAIL);

I want to change this to the user email, but this syntax (from the userjoin.php file) doesn't work;

$mail->AddAddress($_POST['email']);

In the contact.php form the line looks like this;

$mail->AddAddress($to);

but that doesn't work on the usermodifylistings.php

Also, I can't find the send email subroutine anywhere in the usercheckout.php file. Am I missing something? I need to m