Great photo but I cannot think of a caption. When we lived in Montevideo 1957-62 the local bus company had a fleet of Isettas for communication, service and parts delivery, perhaps BEA used Isettas for similar purposes. BEA had the most stylish coaches:
http://s581.photobucket.com/user/Captain_Bubble/media/Picture3-1.png.html?sort=3&o=42
I agree, they were lovely 2 x half deck coaches, when I lived in Reigate as a lad they had a couple of these at the bus garage, out of airport duty then, I think they were used as mobile uniform issuing units. Went to Brooklands in the Bond last summer (not totally off topic Richard) and saw MLL 740, what a beauty, Google MLL 722 and compare.
Strangely enough, outside this very bus garage and at the age of 16 I lost all drive in my Mark D Bond, all the rivets had sheared on the wheel sprocket. A guy getting off a bus said that he had a Bond, I went to see him later and we became good friends, the contacts he had led me to purchasing a Raleigh Safety Seven, wish I had kept it.