Ask if it's working...that seems low for a working mechanism on the desk....

Nice. I think return of product if not functional is a great idea. And, you may have thought of this of course, the producer could then refurbish and sell again. I'm thinking of Amazon warehouse deals where products with flaws are sold at discount. I bought something there. Granted it was new and not refurbished, they do also have options to buy refurbished on there I think.

Ooooh. Good you clarified that. It's not clear in your initial post.

Just spitballing but even asking them to verify doesn't stop someone from claiming it's broken and just not verifying.

What about reversing the payment system and having them pay premium and receiving a small rebate each year they verify? That would definitely handle the problem of faking that it's broken to avoid fees, and might incentivize people also to repair if broken rather than paying for that and then also paying a fee to use it another year. Just thoughts...