I do not think that transfer fee would make sense in this case, Barcelona is already poor and in big debt, which means that spending money on transfer fee doesn't make sense for them anyway, they need to get free agents and youth players from la masia to make sure that they stay afloat. Not only that, but I agree that Silva won't be a cheap player, so it will be a lot of money as well.
Barcelona is very lucky that their manager Xavi Hernandez have accepted to remain at the club beyond the current season so the best approach to improve the club now that they've got limited finances is to invest more in their young players
Yeah Bernardo Silva have blended very well with Manchester City and for sure he is a big player now such that any team that wants to sign him to their squad will know that they will be letting a huge sum off their bag but certainly for FC Barcelona, I don't think they can be able to afford Bernardo Silva because we all are aware of the financial situation of Barcelona now, and even if they will afford him it will involve selling off two players before they can be able to raise money for his transfer but however, Barcelona will not like to sell off two players just to afford Bernardo Silva.
Looking at it from another angle, I keep asking that what really led to Barcelona's financial constraints because this is a club that was blooming in finance before the exit of Lionel Messi just all of a sudden they just fell into financial crisis which has deprived them of making quality signings to the team. Whether Xavi Hernandez remains Barcelona coach or not it will not change the club's current situation right now unless they build up quality players within the squad and possibly sell them off then they can raise up money for the team.