how to bypass lockscreen and reset on iphone 5....... bad ex GF!

Hi guys.

So this is the low down.

I bought my GF an iPhone 5 off ebay...... no problems with it. legitimate sale and every thing was cool. I let her keep her iPhone 4 as a backup, im sweet guy. (bad idea)
Then things turn bad, we break up, but part of the deal is I want the phone back that from her (amongst other crap).

Being the smart ass **** that she is, she gives me the phone back, (minus charger and other accessories, but I couldn't give a rats ass about those.) BUT, she has taken the simcard out and changed the passcode....... saying "have fun"......

So my question is........

Am i stuck with one of the worlds most expensive paper weights? or can i clear/wipe/reset this phone somehow without a passcode/appleid?
I am unsure what IOS its running, i know its IOS 7, im assuming its 7.0.4, but i cant even confirm that.

Help would be greatly appreciated peeps.

Timcee.

Answers