I just don't understand that we allways are concerned about the money we use on players, we shouldn't care, united is a filthy rich club and we have owners that milk the club every year for millions upon millions so I personally don't care if we pay 50 mil for Perisic (even though I would agree its to much for Perisic) but if that is what united will pay for him it's fine with me :-)
A few things here.
1. Any extra money we spend on transfers will in some ways go to strengthen our rivals. Whether it's some other English club or someone we play in Europe doesn't really matter. Either way it's not a good idea IMO.
2. The resources aren't limitless. If we pay too much for one player, then we might get priced out for some other player. For example if we spend 35/40 mil on Perisic, then do we have money to go all in on Mbappe(should we want him)? I doubt it.
3. The players we buy are the players we're going to watch the next few seasons. If things don't go horribly wrong for them(which is even worse).
If we overpay for someone like Pogba or Bale or Ronaldo or Messi(yes, even at his current age pay 100m!), then I don't mind it one bit. I also don't mind it if Zlatan gets 300k or 400k per week as long as he plays well, makes special touches on the pitch, remains funny in interviews and mentors the young strikers at the club.
But I do mind if we spend huge amounts of money on some above average player who will just do things slightly better than the player we have at the club now in his position. And maybe not improve the team at all. I'd rather see us spend 5mil each on 7 under 18 players who can do something special but who are really really raw right now.
I would love Mbappe in United and I still hope we sign him, and who says we don't sign him and Perisic??
We can't have 30 players in the squad. We play 4-3-3 usually with Herrera-Pogba-another in midfield.
Who are the 6 players who you'd want to have in attack? 3 starters and 3 subs.
Currently we have:
Zlatan, Rooney, Martial, Rashford, Miki, Mata, Lingard and you'd add Mbappe and Perisic.
Even if we assume that Rooney and Zlatan won't be here you're still left with only one slot for a new signing. Lingard signed a new deal a few months ago so selling him isn't an option.
We can buy one player to replace Zlatan basically and that's it. Assuming Rooney is out of the picture basically. If he remains, then any new signing also means that one player will have to leave.