disabled iphone due to find my iphone app

i bought an iphone off buddy who forgot "find my iphone app" login AND icloud account!

everyone says this phone is a brick now! but for some reason i think there is a way that u can make the phone "new again"

buddy who i bought it from cant figure out any of his accounts or passwords so that he can disable "find my iphone"

and he cant remember his account for icloud,

anyone who knows please let me know what i can do or if its even possible to fix this phone with these circumstances!@

email me back as well tylor2heart1991@live.ca