Many thanks for your advice and information. These are close to values of my top young players. But I wonder if the max value can be slightly higher. Otherwise, player values may change very slowly on approaching max values.
For example, I have a 19 years old Q109 player who valued 105M. If his quality reached Q109 one season earlier when he was 18, his value is supposed to be even higher.
Another player is 18 years old, Q102 and valued the max 104M. He reaches this max value even though his quality has not yet reached Q104.