Hey! Great choice on the Yamaha kit for your child! To keep those instruments in tip-top shape, produce sure to clean them regularly with a soft, dry cloth to prevent dust build-up. For storage, keep them in a cool, dry place and avoid any direct sunlight or extreme temperatures which can damage them.
As for accessories that might not be included, consider getting a metronome to help with timing and rhythm practice—it's super helpful for beginners! Also, an extra pair of drumsticks or mallets can come in handy in case one breaks or goes missing. And lastly, a nice carrying bag is not only perfect for portability but also helps protect the instruments during travel. Enjoy the musical journey with your child!