First, welcome to YT, and I love the name you have chosen! Sushi is adorable! I don't know what weight Sushi will be when you first get her, but it would be a good idea to pick up some Nutri Cal for Puppies.
Nutri Cal Puppy Supplement
Yorkies have a tendency to get hypoglocemic when they get over exerted, empty bellies, etc. You can pick it up at any pet supply store even Walmart and Target usually carry it. Even though you are going to start out with what the breeder feeds, you might want to go ahead and research dog foods and definitely learn about the grain free kibbles. I couldn't have raised my three through puppyhood without this forum. You will find many well educated people on this board that are willing to help you though any situation you might encounter with your new pup. Contratulations and best of luck to you and Sushi!