It all depends if he joins some other club, or signs a new contract (don't see the second happening). Then it depends if we are in a fight with Spurs (be it for title, top 4 or relegation). If we are, cannot see Spurs strengthening us, if not, maybe 35m should do it. Next summer is 25m if Spurs exercise the +1 year clause, or 0 if they don't. They obviously will unless he gets a career-threatening injury, or they forget to play him for 10% of the available matches.