The problem is how much does the "finished article" cost? £100m? We are not shopping in those places and even if we were, those players want to be in the champions league and if they are not there already they are prepared to wait.
Adding someone like Pepi for £30m can work 3 ways, he can either become a player proven in the premier league and then is instantly worth twice what we paid for him, so we can sell him, make a profit and reinvest, Or keep him and he gets us to europe.
The third way is it doesnt really work out and we sell him back to PSV in 18 months for £15m having written off £15m