Show of Hands

I would say that our store doesn't accept faulty products, but to send it to the manufacturer.

I would prod them a little and if it seems like they are genuine, I'll give the refund. If I can see them cracking, I'll deny them and watch as they scamper away, embarrassed.

Refer to the manufacturer. However, it is better to have happy customers.

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In my experience, having crashed dozens of times and almost crashed hundreds of times, operator error is more likely than technical fault by a ratio of all of those times to none. Putting the thing in a position to get run over by a car *if* it has a malfunction or the operator crashes it makes it seem even more likely that the only malfunction it actually had was operator induced. In any case, even covering avoidable crash damage as a courtesy to incompetent or inexperienced operators would not include covering damage caused by getting the thing run over by a car.

Sure, the warranty covers technical malfunction. But the actual cause of the damage was accidental (the car impact), and that's not covered.

So he was flying it over a road, meaning off his property. That's 100% his own fault resulting from his own stupidity.

Why was he flying in the street?

Replace only once.

If I were the store manager I'd replace it once but "flag" the customer.
The second time around, I'd not believe in coincidence.