Aguero-40
Bastos-12
Vidal- 12
64M
we have enough left for a decent CB, maybe 6m+Momo for Sakho?
Not sure if it is certain that all this money is available for this summer alone or Marotta will have to use part of it for next year too ...
If it's just for this summer, then I'd say you have enough money for Aguero and strengthening the rest of the team in a proper way - will be close, but with good strategy is more than doable.
Sakho is out of reach now, I think. PSG valued him at 20 mil but now with the Qatar thing and their building a strong team, he may well be not for sale at all.
Lugano (Fener seem to be getting relegated in Turkey) would be a very good option for Juve this summer - very established and experienced CB for very cheap.
I think on top of those you mentioned, Juve would need a better LB too, though.