John Lewis, the
retailer blazed the trails (to the best of my knowledge) for
price guarantees, with its
policy:
"Never knowlingly undersold"
Meaning, of course, that if you do find an item cheaper elsewhere, they will refund you the difference.
It is best known to myself, and many Londoners as the one shop on Oxford Street which refuses to entertain any of this late opening nonesense.
Not sexy or glamorous, but sturdy, reliable and with a reputation for quality that your mother would like, it is the Volvo of department stores.