//$variable = $modx->getOption('name', PropertySet, 'default');

  $mailto = $modx->getOption('notify_404_mailto', $scriptProperties, 'to@email.com');

  // E-mail address to use as the "from" field.
  $mailfrom = $modx->getOption('notify_404_mailfrom', $scriptProperties, 'from@email.com');

  // E-mail address to send along as the "reply-to" email.
  $replyto = $modx->getOption('notify_404_replyto', $scriptProperties, 'replyto@email.com');