Second-hand violin for a 9 year old who may quit in three months

My daughter wants to learn violin after hearing a classmate play at a school event. I'm happy to let her try, but I'm not buying a new instrument for something that might last one term, and she'll need a smaller size anyway. Where do people around Financial District or Gachibowli find a decent used one? I can't judge a violin beyond whether it makes a sound, so a shop that sells used instruments with some kind of check would suit me better than buying from a stranger online.