I think John Stones is a fantastic defender, but he did play the majority of last campaign when we were awful in defence. So if an offer of £30,000,000 comes in, then I would bite Chelsea's arm off.
We could use that for 3 team fillers, which are desperately needed. Our first 11 is very strong, but our subs are average at best - and we need money to sort that out.
It doesn't help that a number of players are only staying with us, because nobody else will have them. (I think) McGeady, Hibbert, Howard, Pieanar, Kone.. probably with us until the end of their contract or playing days.