Great place in Tewkesbury called Kustom101. I accidentally found them when getting a new battery for the S3. They are a very decent company. Great chap who ownes it. They have an excellent setup. They had a GT3 porche in having a total, to metal respray....nuts!! Some guy who had it as a track car and wanted it totally re-doing due to the stone chips.
He quoted me £120 plus VAT to do the rear bumper and basically £120 plus VAT per panel. Not sure if thats good, but seemed ok.