Value of Young Players / Server

[FakeFC]

Hello,

I just wonder who set the "basic" cost of players ?

I saw that a friend (on another server, also level 1) bought a 18 years old ST, 5 stars (23) for 500k.
On my server, a 18 years old ST, 4 stars (15-19) cost always more than 1M.
We compared a lot of players and the difference between prices is awesome in our servers. Why ?

Thank you for your Help !