He had an incredible squad at Inter and he spent money there. His win with Porto is certainly one of his greatest achievements though.
He would definitely need a fortune in 2007 when the job was purportedly offered to him, to get them into the top 4 even, let alone win trophies.
It isn't a position to celebrate but it definitely isn't easy to achieve. Other than Arsenal all top clubs have finished outside in the last few years, including Chelsea.
Mourinho is a very good Cup manager but I don't think he can take a squad comprising of only a few star players to finish high up in the table in a League as competitive as the Premiership.