I am level 3 manager and i know that when u levelup your players looses one star but attributes remains same.
I have few questions

1. Player value also decreases when u levelup ?
2. What is the best time to sell players, at the start of the season or end of the season ?


also i have lots of young players age 19-22 who are 4 stars
3. Should i sell these players and buy 5 star players, or keep them ?