How to split page generated by Firestorm Real estate plugin

Hello,
plugin Firestorm Real Estate generates a page with a list of properties using the code below. The problem is that when I enter 50 estates, it created a once long page. I need to split it, but I do not know how. Tag <! – NextPage -> can not be use, because the site with a listing of real estates, have inside only following code [fsrep-listings]. I had the idea to insert tag <! – NextPage -> every fifth cycle, foreach, but it does not work. The source code of finally page contains tag <! – NextPage -> just as commented text.

foreach ($Listings as $Listings) {
                $PageContent .= '<div style="height: 145px; width: 100%;">';
                $PageContent .= '<h3><a href="'.fsrep_listing_url_gen($Listings->listing_id).'">'
                .fsrep_listing_name_gen($Listings->listing_id,$FSREPconfig['Listing Name Display']).'</a></h3>';
                if (file_exists(ABSPATH.'/wp-content/uploads/fsrep/houses/small/'.$Listings->listing_id.'.jpg')) {
                        $PageContent .= '<div style="float: left; padding-right: 12px; height: 110px;"><a href="'.fsrep_listing_url_gen($Listings->listing_id).'" title="Listing"><img src="'.get_option('home').'/wp-content/uploads/fsrep/houses/small/'.$Listings->listing_id.'.jpg" border="0" alt="" style="border: 1px solid #999999;" /></a></div>';
                }
                $PageContent .= '<p><strong>Cena: '.number_format($Listings->listing_price, 2, '.', ',').' '.$FSREPconfig['Currency'].'</strong><br />';
                $PageContent .= $Listings->listing_address_number.' '.$Listings->listing_address_street.' '.fsrep_get_address_name($Listings->listing_address_city, 'city').' '.fsrep_get_address_name($Listings->listing_address_province, 'province').' '.$Listings->listing_address_postal.'</p>';
                $PageContent .= '<p>'.substr(strip_tags(stripslashes($Listings->listing_description)), 0 ,190).'... ';
                $PageContent .= '<a href="'.fsrep_listing_url_gen($Listings->listing_id).'">Zobrazit více informací</a></p>';
                $PageContent .= '</div>';

        }

Thank you for response.