Ok, so the player i have chosen to value today is P. Lahm (thanks to ramaboy for the suggestion) at the age of 29, Philipp Lahm is one of the best full backs in the world. I value Lahm at £15 million, because he is starting to get old now (for a football player) and defenders are generally cheaper than midfielders and strikers. What do you guys think? :)

If Carroll's 35 then he's 38 

Considering his experience, his talent, his versatility and that he's a captain for Germany and bayern I'd say maybe around 25-35mil

Even though he's getting old, he's still an amazing full back.
Captain of both the German national team and bayern Munich
would be a great asset due to the experience and leadership.
I'd say £20 million would be a justified price for him.

Thanks for mentioning me :)

I would go 25 mil or something close... have a look at other defenders around his age- he beats them so easily...

20-30mil

17 million his getting old but his got class more than 20 million is a waste to me

35 mil

35 mil is too much, thats for sure.

16 million on a 4 year deal.