Sanchez was past his best. That was evident and easy to identify because he was a player who was very reliant on his physicality. Kane is 28. He is at his peak but probably for a limited time so the valuation is extreme.
My sense is that City will compete for the title without him providing Foden, KDB and Grealish stay fit but that Chelsea and Man Utd have improved. With Kane I think we would win everything for 2 seasons at least, and the financial value to City from the additional revenue that would generate makes the transfer justifiable. In some senses even at £150m we would be stupid no to do it. This is a case of money gets money. If you have £150m then here is an opportunity to earn £300m. Winning 1 Champions League alone is worth £100m plus intangibles. If you value the player in comparison to other players transfer valuations then because of his age he is over-priced.
If City sign Kane then we can become England's largest revenue generating club if United continue to struggle and once you are in that position you control your future.
I think Spurs will sell Kane because they are under financial pressure, and selling Kane for £130m will allow them to rebuild. Keeping him does not make much sense because in 2-3 years time when his game starts to dip they will have big problems and there is likely to be some fallout. However, Levy likes to be the strongman and has shown poor judgement in the past so we cannot be sure he will relent. It would be wise to line up alternatives such as Lacazette should we judge the transfer is unlikely to proceed.