Greyhound grow up to 30 inches tall which have great speed. In fact they are considered one of the fastest of all dog breeds with very sharp eyesight. These are gentle though which make them suitable for apartments. They are loving and dislike being left alone and love kids. Grey Hound however is not suitable for cold climates, they do well in hot weather. As mentioned speed being their dominant trait, it needs good exercise. In spite of its high energy levels, amusingly they love to sleep.