Yep, all main dealers see a woman and think we'll rip them off. We also fit 2nd hand ebay parts and charge full whack. It's how we make our margins. Only we don't. You're much more likely to be misdiagnosed and ripped off by your local mechanic who fits none genuine parts made of chocolate and then sub contracts it out to a dealer to fix his mistake and adds 10% to your bill. I've never worked for Mercedes to be fair but all manufacturers generally have 'goodwill' available to customers where by they offer a percentage towards the repair on cars just outside of the warranty. It's worth asking the question. Of course, if it was done at an independent you can go to the motor ombudsman if they are a member which most garages are.