Porsche Bodyshop Recommendations

[Ravi944]

My much cherished and beloved guards red 1990 944 S2 is in need of some attention around the sills and rear wheel arches. While not serious, I would like the job to be done professionally from the outset to minimise chances of re-occurence. Can anyone recommend a professional and thorough bodyshop somewhere within the 20 mile radius of E. London? Additionally, are the approved bodyshops considerably more expensive? Thanks