Having all the money in the world can buy you all the material things that other people can only dream of. One of these is the capacity to have a carmaker make a car that is uniquely your own. It can be the most beautiful sedan in the world. You can also ask them to build you the fastest supercar the world will ever see. Though if you really want something built just for you, you can have your auto builder engineer the craziest cars that he can think of. This should make it fun and one-of-a-kind.