What works in a barber shop
A stamp per cut, the tenth free, with the beard trim as a half stamp if you like. The card sits in the Wallet between visits, and the dashboard's "about to lapse" list shows who is overdue against their own rhythm: the four-weekly client who has not been in for six.
Reviews matter more to barbers than to almost anyone. The stand by the mirror asks on the way out; everyone gets the same two buttons.
The card works whether they booked or walked in. Scan at payment, done.
A push to members with no visit in five weeks: "Chairs free this afternoon, £2 off for members."
A points card for the pomade and the beard oil, if you sell them.
Put the stand by the mirror
Fifteen minutes to set up, three seconds per client.
Questions
Several barbers rent chairs. Whose card is it?+
The shop's, with a staff PIN per barber so every stamp is attributed. If a barber leaves, their PIN is revoked and the clients stay with the shop.