1. The law of similarity, proximity and figure ground are been used as well as white space.
2. The logo, navigation, image slider/images that feel like they are been animated, a headline/header and search bar that both grab the visitor's attention.
3. Images are used to show what the apartments look like and also to illustrate what an article or header is about.
4. The website makes good use of axis of interaction a lot and primary buttons too.
5. Sans serif font is used mainly, a lighter black color for the body, and darker blacks for headers and subheaders on different pages or parts of the website. Reds are used for buttons that let the user request to book a place and other colors are used to catch the visitors eye while looking at information about a place.
6. I would say the only thing that seems is been animated are the sliding images above the fold.