I'm not sure about the situation at Inter. I think they all have some say in it and contrary to the typical Serie A dealings Mourinho seems to be in charge of their transfer policy.
My understanding is that a manager has ideas of who he wants. he tells the sporting director, who tells him if its possible, and offers his own opinion, sends his scouts to keep tabs on the player...the other routine is this: the manager and sporting director discuss what is missing, then nail down what they need, not solely WHO they need...scout sent out, makes reports, a list of players who fit the bill and are viable transfers is given to the manager, who then discusses with the sporting director, how, if at all to, to proceed.
That is how I used to think it happened at all clubs. Not just in England, or in Italy...if this wasnt the case, then I am shocked that I have not heard any more often than in other leagues managers who have managed in italy, complaining after leaving a club that mr X signed these players, i didnt want them, the team went shit, its not my fault...I remember Didier intimating similar problems after he was shown the door, or left of his own accord.
The closer the sporting director is to the manager, the better. the wider his network of scouts/spies, the better.
But I really don't see the evidence of now or yesteryear, for the general consensus view that in Italy, transfers are decided by the sporting directors, not the manager.
When a sporting director has more say in squad personnel than the manager, he becomes more the manager than the manager...hohohooho! or something along those lines. That may be acceptable for Ciro...or very young coaches...or small name coaches going to big teams...but to proper managers, it is an untenable position, surely.
It can't be a case of 'we will give you a group of players...you make them win, allenatore'...or is it???