SAMSUNG GALAXY S3 BRAND NEW SEALED WHITE UNLOCKED ?

HI IV GOT A BRAND NEW SAMSUNG GALAXY S3. IT WAS GIVEN TO ME TODAY AS AN UPGRADE BUT I ALREADY HAVE AN IPHONE SO DONT REALLY NEED THIS. ITS HE LIMITED EDITION WHITE VERSION. IT COMES FACTORY UNLOCKED AND IT IS A BRAND NEW SEALED BOXED HANDSET. CHEAPEST YOU WILL FIND FOR A BRAND NEW S3 ESPECIALLY WHEN THE RETAIL VALUE IS WELL OVER 550 LOOKING FOR QUICK SALE. PRICE IS NOT REALLY NEGOTIABLE AS THIS IS ONE OF THE CHEAPEST ON GUMTREE. WILL CONSIDER A SWAP BUT WANT CASH ON TOP AND SWAP ONLY FOR IPHONE 4. BASED IN HOUNSLOW.WEST LONDON NEEDS TO GO ASAP. SERIOUS BUYERS ONLY. THANKS