my 2 cents
Based on 米大's saying, the RMB will be 100:1 again USD. Even if this happens at that time, will the money of your parents change if they put it in the bank? What if they buy that 地下商场, based on the inflation happening in China, will the value decrease because of RMB is 100:1 again USD? I believe that is the direction you can think about how to invest with your parents' RMB money.