I work in Longford, it's about a mile or so from Sipson and borders the northern runway of Heathrow Airport. I don't recognise that frontage although there are still some old houses and pubs standing.
Staines, Sipson and Longford must be fairly close to each other then, which makes sense so far as the Starnes family is concerned. Or, at least, my branch of it. It's difficult to date the photograph, but c. 1900 would be close since Percy Starnes appears to have emmigrated to the US in 1907, and made several trips back and forth in the preceding years. It would be nice to know the address of the Longford Post Office in 1900. O for a set of Post Office directories!
Patrick