Have just been involved on Facebook in helping to research the location of a shop in Snargate Street in the early 20th century for a lady in New Zealand whose forbears came from there. It was immediately opposite an establishment named the Bon Marche.
If you look at the building in the old postcard with the stripy red and white awning and an unusual curved alcove balcony on the top floor, this was the Bon Marche, the ends of the name can be seen in huge lettering on the side of the building.
Looking at the street numbers on an old map I suddenly realised that the Bon Marche still exists and is the old part of the now closed Seafarers Centre at what is today nearly the end of Snargate Street. I slept in there on many occasions in years gone by!