The online powerhouse is ranking properties on a one to five-star scale — where a five-star rating signals that a property has the most overall appeal.

Booking’s move is bold because the travel agency giant is rating the properties itself. Until now, rentals have gone unrated. That’s put vacation homes and apartments out of sync with hotels, which third-parties and governmental organizations have long categorized by star ratings. The star ratings are separate from a property’s average score, which continues to be driven by customer reviews.