"How wonderful to knock on someones door with a policeman (if you can find one)and say "Excuse me can I have my concertina back"!!"
Hmmm, that's almost too good to let go thru to the keeper... but I'll be kind...
I suppose though that I could then take my piano accordion out in public with no fear. Even leave it on the back seat of the car with the window down, and not worry that when I return, there won't be another three alongside it?