The police turned up eventually and did the old rolling eyes, 'how could you be so stupid' routine but it's quite a neat little con because he tells you he lives in your block and chances are if there are 10 flats or more, you don't know all your neighbours anyway. Then he shows you his sponsorship form and if one of your neighbours has already signed up, then you think he must be ok because your neighbour's given him cash and on it goes. Anyway, still feeling stupid but at least we got our money back.
The police said he has also been operating in Kennington so between there and Shad Thames, looks like he's fairly prolific in the SE1 area.
Why oh why do people let these guys into buildings in the first place. Tradespeople will be let in by their employer. Delivery people will be let in by the recipient or leave a crad to re-arrange delivery. Anyone else should be ignored. Letting people in is soooooooooo annoying.