McCarthy did, however, suggest that the money from Cresswell's sale could be used to lure bigger names who demand steeper wages.
"We're not going to be going out and buying anybody or paying money for anyone," he told BBC Radio Suffolk.
"It will be Bosmans and loan deals. We've done it so far, but what we have got is funds for wages."
Since McCarthy took over in Suffolk in November 2012, he is yet to spend a transfer fee on a player.
Last season he guided the Suffolk club to their highest finish for five years.