https://relaunch.pdir.de/docs/en/contao/extensions/maklermodul/requirements/Note The real estate module is compatible with Contao 5 and 4. Contao 5 and Contao 4 Contao 5 requires a web server such as Apache or NGINX with PHP and MySQL support. Our real estate module requires Contao 4.13 or Contao 5.x and PHP 8 or higher.Hugoen-US