this sign is lovely. i suspect it might be slightly tongue in cheek (since it was no-where near Greenwich). It says (with extra apostrophes):
Have you seen this bin.
Substantial reward offered for information leading to it’s return
On the 26th July this wheelie bin was heinously stolen from a house in Greenwich by people who obviously have absolutely no respect for the feelings of others. If you have any information about it’s whereabouts please call the number below. You CAN make a difference.
CALL [number] – in the strictest confidence