Last month, we had an incident at my business where one of our new guys put diesel (instead of petrol) into two jet skis. I noticed this once he'd started putting the diesel in the second jet ski and immediately told them to stop and not to start the jet skis under any circumstances. The couple who own the jet skis were understandably not happy (well one of them was reasonable, but the other was very angry). What I did next was try to fix the situation: 1. I offered to refund the cost of the fuel 2. Paid for a cab home for them 3. Arranged safe storage of the jet skis overnight while we arranged a trailer for the jet skis to be taken back to their chosen jet ski supplier. 4. Said we'd pay for the draining of the diesel and refilling with petrol. I called them a few times at regular intervals over the past couple of weeks but didn’t get a response. Then yesterday I got an email with an invoice/quote for just over $10k! The bill is for things like replacing all the fuel injectors, replacing the bumpers, replacing the mats of the jet skis. The jet skis weren't new, they had some wear and tear from being used jet skis. All they’ve said is that I should pay for all this as the jet skis were damaged while in my care overnight and they’re not going through insurance. I have witnesses who saw the jet skis before and then when we sent them back - we didn’t do any damage and would only expect to pay for the draining and refuelling for both jet skis (and doing the these I mentioned above to try to do right by the situation). I think it's bull, and they’re trying to take advantage. I’m a good person and of course I want to do the right thing by fixing the issue my staff caused by draining and refuelling properly, but not pay for them to completely refurb their jet skis. There’s another jet ski provider that I know and have the number of - I was going to call them for an independent quote. What does everyone think? What else should I be doing or not doing under Australian Consumer Law? Thanks in advance for your help.