hello I have a Q7 2013 reg SE and I would like to upgrade the front headlamps to xenon lights/Sline lights package please and don't know where to start. Few questions 1) costs involved ? 2) what do the need ? 3) any suggestions who can fit these close to London or West Sussex area - I don't mind travelling provided it's a well recommended person and don't cost an arm and a leg 4) how much will the existing lights sell for and where to sell these other than eBay / Facebook ? Anyone gone through this process - inputs would be much appreciated ?