Carvalho can sign a pre-contract with an English club one month prior to his current contract's expiration date; he can sign a pre-contract with a non-English club six months prior.
I think the squad needs four positions filled next summer: back-up right-back - probably Bradley, back-up 6, starting right-sided 8 & left-forward option.
I think Aurélien Tchouaméni & Christopher Nkunku would be suitable profile players for the 8 & LW.
What is the going rate?
We are now in a market in which, aside from state-owned clubs, there are very few options for a player looking to leave a leading club for one in which he will compete for trophies and be paid more. Look at Messi & Ronaldo in the summer, Lewa's contract position and Sterling's manoeuvres.
Shaqiri to O'L edging closer.
Lyon have loaned Emerson from Chelsea which allows them to sell Cornet to Burnley thereby securing the monies to sign Shaqiri.
It is a risk not to sign a fourth centre-back.
It would also be a risk to sign one as doing so would curtail the space within which to develop Hoever, van den Berg and Koumetio.
Milot Rashica is available for around £15m if Werder Bremen are relegated; they are currently second from bottom, two points off the relegation playoff place.
El Desmarque reporting that Diego Carlos is set to join in the summer from Sevilla; £64 m buy-out clause activated ahead of Real Madrid. He's a 26 yo Brazilian CB.
Reports that Liverpool are to sign Sam McCallum; a 19 year old English left back from Coventry City in January and then loan him back for the remainder of the season.
The difficulty for Palace with regard to Zaha is that the player wants to sign for a club in European competition and not have to move away from London; it's problematic to create an auction involving one club with no money (Arsenal) and one who won't spend any money (Spurs).