1). Cartier Secret
Price : $ 2.75 million

The watch is made of White Gold made out of 18 carat white gold plated with rhodium. It also shows the 3.53 carat portrait cut diamond which makes it looks glamorous as well as trendy. To make it more luxurious it is covered with 3010 brilliantly cut diamonds. All these features makes it most expensive.

2). Patek Philippe 1953 Heures Universelles Model 2523
Price : $ 2.9 million

This watch is the most preferred watch in the community of rich peoples. This watch was auction in the year 2006. It is made up of 18 carat yellow gold. It features a polychrome and enamel dial which resembles the North American continent. It is also included in the list of most expensive watches.

3). Piaget Emperador Temple
Price : $ 3.3 million

Piaget Emperador Temple was listed in the top 10 luxurious watches. The Piaget Emperador was made up of expensive diamond in which
a). First Watch contains 207 baguette cut diamonds, 481 brilliant diamonds and emerald cut diamond
b). Second Watch contain 11 baguette cut diamonds and 162 brilliant cut diamonds.

4). Patek Philippe 1928 Single Button Chronograph
Price : $ 3.6 million

The Patek Philippe 1928 Single Button Chronograph was made up of 18 carat pure white gold. The dial of Philippe 1928 was designed with silver matte. It was manufactured at the time of crash stock market in 1928 after that it is also known as one of the most important patrons in Patek Philippe.

Nice one.
Two things though:
i. you didn't complete the list
ii. the order was reversed