9 — Polo
Polo is an expensive sport and you will need to buy an elite horse right away. In addition, prepare your wallet to pay huge sums for training, traveling, and maintenance costs. Polo is a very unique kind of sport, as you will have to purchase more than just one horse. Since you will need to substitute a horse that just got tired, you might end up buying up to four horses over time.
8 — Formula 1
Formula 1 drives have to pay a lot of money each year just in medical costs related to injuries. Since this category is the peak of motor racing, you will have to start practicing at a very young age in little go-kart. As to category level, the higher the category, the higher the costs.
7 — Sailing
If you want to practice sailing, you need to have deep, deep pockets as the costs of boats and related equipments is very high. For instance, a top-notch vessel might cost up to $100 million which is pretty high even for many millionaires out there. In addition, getting a place to store your boat will be really expensive as the vessel will not be used for most of the year.