Uninstall WP Hotelier
To uninstall WP Hotelier simply go to the Plugins page, find WP Hotelier in the plugin list and click on the Deactivate button. After the deactivation, click on the Delete button.
To delete ALL the data installed with WP Hotelier from your database (rooms, settings, reservations, etc) go to Hotelier > Settings > Tools and check the Remove Data on Uninstall option.