Well over £15m Cortese always strikes a hard bargain, Oxlade-Chamberlain went for £15m when we were in L2. I don't think many of our players, like your own, would be looking for a move away from the club. Besides you have Coutinho, bought in at £8m?
Can't see him going anywhere in January, especially if you're still hovering at the top of the table and he's getting regular football with the WC coming up. Would make no sense for him to move and sit on the bench at a "bigger club" for the rest of the season. Come the summer that's when may struggle to keep hold if the top clubs come in for him. I doubt we will be one of them though, the amount he'd cost would probably be most of our budget and I don't know if he's ready to go straight into our first team to improve the team which is what we need.