The same goes for friend, neighbour, family member of course...
If they damage an item of your property, say accidentally drop your phone in a puddle, reverse into your car, knock over an heirloom etc... pure accident, no carelessness, where is your forgiveness limit?
Obviously, a good person would volunteer the compensation immediately, and you may instinctively waive it because it's not lot of money... but if it is a moderate amount, where is your "I'm sorry, but..." limit for a pretty good relationship?