Scott Cariss

if(!empty($_SESSION['s_property_region'])) {
    $sqlWHERE .= " AND property_region = '".$_SESSION['s_property_region']."'";
}
if(!empty($_SESSION['s_property_bedrooms'])) {
    $sqlWHERE .= " AND property_bedrooms = '".$_SESSION['s_property_bedrooms']."'";
}

$metas = array(
    'property_region', 'property_bedrooms'
);
foreach ($metas as $i => $meta_key) {
    $meta_fields[] = 'm' . $i . '.meta_value AS ' . $meta_key;
    $meta_joins[] = ' LEFT JOIN ' . $wpdb->postmeta . ' AS m' . $i . ' ON m' . $i . '.post_id=' . $wpdb->posts . '.ID AND m' . $i . '.meta_key="' . $meta_key . '"';
}

$sql    =   "SELECT $wpdb->posts.ID, ".join(',', $meta_fields)."
             FROM $wpdb->posts
             ".join(' ', $meta_joins)."
             WHERE $wpdb->posts.post_status = 'publish'
             AND $wpdb->posts.post_type = 'property'
             ".$sqlWHERE."
             ORDER BY $wpdb->posts.post_date DESC";