With every other shop in London and the rest of the UK closing down, why don't artists and crafters take to the streets with affordable electric vans and mobile units, going where the crowds go to find their customers. No high rents, small overheads, no waiting around in empty shops for customers, be your own boss when and where it suits you! All manageable online.
I think there are some types of laws that prevent that type of street selling thing, similar to the way buskers need to get licenses. You know how HMRC are, don't like anyone to start taking cash in hand and avoiding their tax liability...
There are some sites out there though to the rescue of small talented artisans! Etsy.com is one example of these minority producers banding together to get a voice against the loudspeakers of the big players. Maybe there are others, it's just one I've come across, but it could be a market/model worth exploring?
ahh... not technical but can provide information regarding taking to the street with moving vehicles!! we have a cart* http://www.flickr.com/photos/henryandjayne/3077890198/in/set-721576... that we have taken into cities, towns small islands etc!! you need a pedlars license... their are hundreds of different sorts and lots of silly rules but all are get roundable!!
unfortunately because i was unable to construct with my iphone i did not.... a friend made it!! it was quite amusing taking it around the highlands and islands!!