Neville believes that, despite missing out on Inter Milan winger Ivan Perisic in the closing stages of the window, Mourinho will still be content with his side's business over the past couple of months.
"I think he will be satisfied," Neville told Sky Sports News. "He was very clear from the beginning he wanted four [players]. "Jose is usually outstanding in the transfer market and he has proven it again - to get [Nemanja] Matic. Even [Romelu] Lukaku when he signed, it was on the edge of too much money, but when you look back now it looks like a good deal.
"They needed a centre back and they got Victor Lindelof, they have got Zlatan Ibrahimovic back. He wanted a wide player in Ivan Perisic and he has not got it. But he understands ultimately that you cannot get everybody you want. What I would say about United is a couple of seasons ago, you could be immensely critical of United's transfer policy as it was all over the place.
"They were signing players who one, should not have been at the club, but who did not fit the profile of a Man Utd player. What I have seen in these last 12 months is the players that have been signed - [Paul] Pogba, [Eric] Bailly, Matic, Lukaku - in my mind they fit the profile of a United player in their strength, personality and character."
United currently top the Premier League standings after three games as they seek their first title success in five years.