Ingenuity needed retrieving item dropped through letterbox

[robbocop33]

Mission is to retrieve small jiffy bag with a key inside that has been dropped through a household letterbox.I need the key to cut it and program it for a customer,and postie has dropped it through the flat next door,which is unoccupied!:-)
It has one of those cheap bendy plastic white front doors,anyone any ideas?

[robbocop33]

magooagain said:

Look at the OPs username,he could be a goody or a baddy!

Just to clear that up,second name is Robertson,nickname is Robbo,struggling for username when i first went on t'internet and!,well that's what popped into my head,oh,and the 33 is for the amount of houses i've broken into this year with all your help!!:-)