For me, we only have to look across the city. Thiaw, Kalulu, Vranckx, Ballo-Toure probably cost Milan about 5/6m combined, but I'm sure they'd be able to sell them on for 5m+ each.
We appear to be simply incapable of doing anything like that - finding somewhat decent, unknown players at low cost. Asllani was 14m (and doesn't play), Bellanova would cost 7m and he's terrible, Bastoni cost 30 odd million, Onana was known globally, Lautaro cost 20m, etc. etc.
We appear to wait for a player to be completely out of our price range or utterly overpriced before making a move. And even if we identify them, as apparently every damn player in the world was on Ausilio's list before going somewhere else, we don't get them!
Our squad is old, our owners are broke, and our management is either out of ideas or has objectively horrible ones. So selling Bastoni or not selling Bastoni seems to be a moot point, we're gonna be ass regardless until Suning leaves.