My Sister-in-Law did that with a refrigerator.CYA at all times Peter!
Been there and sadly got the T Shirt early on which taught me a salutory lesson. As a result of that encounter with a very well known luxury watch dealer I started to video and photograph everything. Especially as you know that any faults will be dismissed as 'that's normal or within specification Sir.' Which is dealer speak for 'run along little man and mind the door on the way out'.
I had a particulary amusing encounter with my Dealer and my brand spanking new 'The Best 4x4xFar'.
It had so many faults which they dismissed or attempted to put down to user error. Until I showed them the film I had made on my laptop over 6 months worth of visits....... and which was going on Facebook that very night.
Oh how we laughed as they phoned the decision makers and my POS was bought back.
Illegitimi non carborundum!
She caused great consternation, when she showed documents proving not one or two service calls, but five or six.