Lukaku took a massive pay cut for the remainder of his contract prior to the Roma loan being agreed so selling him will be a hell of a lot easier in the next window than it was last summer or in 2022. The renegotiated salary package also included a 35-40M€ release clause in Lukaku's contract which can be activated by his current loan club Roma or anyone else. Whether we get the full release clause amount or something a bit lower is a question mark but he'll 100% be gone for good in a matter of months. He's also started flirting with the head choppers in recent weeks so might even go there for a retirement fund but he can definitely stay in Italy and continue earning a more modest wage if he still fancies playing in Europe.
Ziyech is already gone. The loan to Galatasaray is said to include an obligation to buy him. The fee will be nominal at best, maybe even a freebie, but he won't be returning.
As for Maatsen, Chalobah, Broja and Hall it remains to be seen how much they'll bring in. Hall's loan to Newcastle already has an obligation to buy for £28M so unless something really drastic happens that's more or less guaranteed, Maatsen's loan to Dortmund has started brilliantly and I don't think there will be a shortage of takers for the £35M release clause included in his revised contract.
Chalobah has also attracted plenty of interest both in England and abroad, but his injury problems this season have so far scuppered the possibility of a deal but I could easily see him fetching £15-20M as well. You mentioned we couldn't sell Broja in the January window but did you see how very little transfer business was done in the EPL overall? Every club seemed almost afraid to spend any money, but I doubt that's going to continue once the summer window comes around. He's on loan at Fulham now and if he plays decentlyover the next months there will almost certainly be clubs interested in signing him in the summer and it's only going to be a question of how much the club are demanding to sell him. If there are some serious FFP concerns, the fee will naturally be on the lower end but if the club are in a position to stick to the valuation and there are still clubs interested it could raise his sale price.
So let's see: Hall £28M, Maatsen £30-35M, Chalobah £15-20M, Broja £25-35M, Lukaku £25-35M, Ziyech free transfer
All added up a conservative estimate would be £120M and could even go as high as £150M. Feel free to save the post and quote me at the end of June and we'll see who's right and who's wrong.