We paid 30 million for Sissoko - who was coming in as a squad player.. and that's a few years back.
We also paid 40 million for Sanchez and 30 for Lamela - who were purchased as first team players but worked their way into the squad player label which is a bit different.
Nothing to say about the Watford lad being worth that, but I do think we are looking to spend on the 'squad' this season - so I wouldn't write off the idea of paying 40m+ for a squad player.
After all - if Levy signs them, presents them to Poch, and he doesn't fancy them for whatever reason - they just become squad players. There's no guarantee that Lo Celso will be playing every game as he will be needing to keep Dele, Winks or Eriksen out of the team most likely - which shouldn't be easy.