Licha, with the crazy money it's spend on any role nowadays, to have a player that it's that talented and gets the club, there is no need to sell him even if he is worth that money or not, the route it's just to find a suitable high level partner.
And even if not worthy 100 now, dunno what United can get for such an ammount in the market too, on principle nor Mainoo, Hojlund and Garnacho should be sell... Yet it's not like they look like some sort of certain thing like Rooney, Aguero or Neymar since a very young age, so 100 it's really tempting with these while today they are in some sort of grey (yet promising) area.