5S iCloud removal

I have an iPhone 5s locked to the UK O2 network. It is also iCloud locked. Ive read and was told by many people you cannot get around the iPhone iCloud lock but i have seen on this site and one or two others that you can pay to have iCloud removed.

But there is so many different services ranging from 9 dollars to 200 dollars. Im not going to spend a fortune as the iPhone cost me 60 pounds and its not even worth much more…

Can someone explain where I stand, how much its going to cost and what way these sellers get it unblocked…..