Really interesting idea! I think the URL part might be the trickiest, since it assumes that the customer has the phone next to the laptop/computer and also that they would be comfortable with using the workspace. Through my interviews I found that people who are 50-70 don't really care much for fancy interfaces and stellar customer service, they just want their errands done as quickly as possible. That being said, I think your idea is really really cool, but you might want to consider an alternative to the web interface aspect.
Hi! This is an interesting idea, very similar to one ofours: Branch on Wheels Have you developed this further? We were initially thinking about developing one of our other ideas (a digital product) but we revisited it and decided a service might be best. Would love to keep in touch about where you decide to go with this!