Sounds about spot on. He was fairly convincing in that he added some patter that means he has at least put some effort into his scam!
Anyway, just to confirm, there were no window cleaners around and none showed up at our house before the time he gave me (which, thinking about it, gave him just enough time to visit some local streets before scarpering).
Oh, the only other identifying feature I can give is that he had a Millwall FC ring on his right hand.