My cleaner was doing a bit of ironing for me yesterday and after a while she said the iron had died. There was a stack of ironing to be done so I went across the road and borrowed an iron from my neighbour (and good friend).
My cleaner didn't say anything when she left but this morning when I took the iron back I noticed a big brown mark on the metal plate. I asked my neighbour if that mark was there before and she said no and it was a fairly new iron! 
I apologised profusely, offered to replace it etc but she said she would see if it came off.
I emailed later in the morning (about something else) and apologised again. I really want to do the right thing and I feel very bad. I was thinking I would buy her a £30 Argos voucher or something.