Today there was a news about PSG wanting 25 million for Icardi, and Icardi wanting 8 million for his salary as well, which we all know Galatasaray, nor any other Turkish team could ever afford, that's just not possible.
I am not saying that is the end deal, that's the start of the negotiations and we could see more like 15 million to 6 million, which is quite possible, but even that would be too much, it would basically be a deal that will not profit them at all, Icardi could be bought for that much, which would be very very difficult and probably won't happen, but even if it does, they can't play him for a few seasons and then sell higher, they will make a loss on that deal, bad deal even though he is a great striker.
I think 25 million isn't that huge comparing his feet to many other strikers in European football (as we did in other posts). But can Galatasaray afford it? Well.. actually they can. But it means they need to give 2 good players (overall good player would be worth 10-12 million in average) to get 1. Not a good deal. I think with negotiations they can do 20. But its still too high. Board should try hard to make that value 15 so it may be more affordable.
I think he doesn't worth the 25 million request tag because if he was worth that much, he would be in a big league right now, not in galatasaray. I think 15 million is more likely, and that means if Galatasaray sells one of their good players like Kerem, and then the rest could be paid.
They could find a buyer for Kerem at around 10-12 like you said, and the rest would be fair to pay, salary would be a bigger problem, because it would be hard to pay 6-8 million for a single player, but he is one that they really need and he could change the team for better all by himself with how he is scoring and assisting. At that point all they need to find is a replacement for Kerem.