paying for borrowed item

Question:

Hi, thanks a lot for your website I find it very informative and interesting.

My wife lent an electric nursing pump to a friend, and her friend lost it. She couldn’t find it so she told my wife to buy a new one. The pump cost us about £80 when we bought it new about two years ago.
now it is a bit more expensive.
My question is, how much should her friend pay us, (she told us to ask a shaila). Does she pay the amount we paid for the pump, or the retail price at the time that she lost it? Or does she pay much less as when she borrowed it, it was already used so its market value was as a second hand item.
Thanks

Answer:

Hello,

A person who damages a used item doesn’t have to pay the owner back a new one, as it is not the value that was damaged. Exactly how to determine this is tricky and I would need to know the details how old and used it was, etc.

Best wishes