Where do I start?
Man. Utd paid more than that for Rojo and a lot more than that for Fellaini. Hell, they paid £30m for Shaw.
Kane has just scored 31 goals, 21 in the league, despite not starting in the league until a good chunk of the season had elapsed. On top of this he has scored 9 goals in his last 12 international appearances and has just been voted Young Player of the Year. He's two-footed, scores every type of goal, puts in 100% effort every game, is a model professional and dedicated to getting better and better.
His all-round game is excellent (he doesn't just score goals), with no real weaknesses. He has reasonable pace, holds the ball up well, good passer of the ball, is strong, tenacious, good at dribbling and composed.
And apart from anything else he has just signed a very long contract at a club that he doesn't want to leave, which doesn't need money, whose chairman doesn't wish to sell and is known to be a tough negotiator to the point of recently getting a world record fee.
And you say, in the face of all this, in a league that's awash with money, that Kane "should be no more than £20 million" ??? The mind boggles.