actually i see it in a different way Ahmed ,
we have several assets that are decreasing in their values:
Almiron for example we bought him in an inflated marked and we over paid him moreover having several disappointing season also affected his price, age also taken into consideration : value = 2.5m
so Almiron+2.5 = 5 mil
Criscito is a different story, economical wise too, as an asset which increase its value with starting in WC holder increased his price+ the induce force of the asset or the player himself of playing at Genoa limited our asking price for him so a fair price for his half is 5 mil.
so overall, Bonucci price is actually 10mil even if its high for a CB, but you have to take into consideration that this is only -2.5mil in cashflow.