Site: Beatles' Apple Boutique - Baker Street (2 memorials)
W1, Baker Street, 94
This was the site of the Apple Boutique (7 December 1967 - 30 July 1968, building demolished and rebuilt). See View from the Mirror for a picture of this very 60's shop.
The Lennon plaque was erected in 2003 and then replaced in 2013 by the Lennon and Harrison plaque so it seems that Heritage Foundation have chosen this site to commemorate dead Beatles. We hope it's a long time before they have to change it again.