Have him pay you back $150 or so over maybe a 6 week period. That way you get part of your loss back, it doesn't take too much out of his pocket in one shot, and he is now aware that he should take better care of your stuff when you are a nice guy and let him borrow something.
Let him pay back so much a week, unless he quits. Then the unpaid balance comes out of his last check. What ever you decide, put it in writing. Have him and you both sign it. It's amazing how much weight that piece of paper gives to an agreement.
The only thing you should have been involved with is when he came up to you with a brand new exact replacement in the box along with the explanation.
Doesn't it just make sence that if you borrow something that isn't yours and you break it or lose it then you replace it? This is a simple question without need for a massive discussion. Take responsibility for your actions.
Why should you have to pay anything for his error. You were good enough to let him borrow it and good guy or not he let you down. Now you feel as if you have to give him a hundred bucks because of the error. That trimmer was used but it was not finished with its useful life. 30 hours or not it could have brought in much more profit. Now you have to replace it and you will not get one for 150 dollars.
He should have just sucked it up and bought you a new one, the mistake is on him not you.
You loan equipment without a rental fee for wear and tear on equip?
At $240 with only 30 hrs on it, it cost you aprox $8/hr to opperate add another $100 to that and your new opperating cost sky rocket to a wopping $11.63/hr not including time spent buying, advertising, etc... or jobs turned away until matter is sorted out.
I say he pays full price. It's not like it was on it's last leg and you were going to buy a new one next week.
In the future I would have a stipulation that anything borrowed will be replaced at full value. Cover your bases.