For scratches, CP Panelcraft at Addington, not the cheapest but they are an Audi, BMW & Mercedes approved bodyshop.
For dents/dinks, DentFX at Epping Green, Aaron is amazingly skilled with dents and dings. He sorted out a pig of a double rippled dent on my car that had been the subject of a previous bodge.
For Alloys, not sure, I need a good "alloy man" myself.