I doubt very much that we would consider selling him UNLESS he himself asked for a move, which I believe is unlikely. IF that was the case, I reckon we would be looking for around £15 - 20m at least (especially seeing that the likes of Henderson went for £20m!)
It's clear that Roberto rates him highly, despite what some people might want to believe. Here's an excerpt of Mancini's comments (from The Guardian) after the recent Wolves Cup game...
''....I am happy he is upset," said Mancini. "I love Adam. It is like with the children in your family. If you love your children, then sometimes you should be hard with them and Adam understands this. I say what I want because, if he were not a good player, then I wouldn't waste my time on him. But because he has everything, I don't want him stopping at this level. I want him up a level and then a level more.
He has some characteristics that are different from other players and because of this he could become one of the top wingers in the game. If you have a top winger, you are going to win a lot of games. One versus one, he is incredible, every time he takes the ball out wide near the box, we can score a goal or at least have a chance."
WE LOVE YOU CITY.