If we go from the rumoured players of the likes of Higuain and instead just by Barry who at his best 4-5 years ago was a ridiculously limited player, he's since lost his "pace" when he barely had any to begin with and is basically a joke of a footballer who would likely ask for pretty hefty wages... dear god no.
Pepe, thug, he's incredibly athletic and can bomb up and down the field like a demon and I actually think he's better suited to the DM role, maybe like Luiz, because he's great on the break. But he's a thug and a cheat and I'd prefer not to have him anywhere near the league, he's not a brilliant footballer, fully capable of a great last ditch tackle but more due to pace. He gets away with an insane amount of woeful tackles that should pretty much be red cards but because he doesn't get booked gets seen as great defending. HIm and Ramos, no idea how they don't get sent off pretty much every game.
Benteke, in business terms I'd say he's worth a punt at 12-15mil but 20mil would probably want beyond one good season. Because one season wonders are pretty common, guys who can do it for 2 seasons are a much smaller group and 20mil after two good seasons is a much better risk.
For right now I'd take Higuain for 25mil, if Benteke is actually good still in 2 years we can always go for him then.
Buying 1 or even 2 season wonders seems to very rarely pay off, ie you buy 5 guys for 15mil after one good season and 4 turn out to be crap and not worth even 10mil and one ends up worth 30mil. You've spend 75mil, got one 30mil player and 4 x 5 mil players, so spent 25mil more than you should. if you just wait and buy the one player for 30mil 2 years later... you've spent 45mil less and still got the one great player and this ignores the inflated wages the 4 flops are on meaning no one will buy them for 4 years and all the money wasted there. Buy guys young with potential, or finished product, not inbetween when its most risky IMHO.