But in reality you would face similar issues. How would people prove they destroy a camera? Show it to you? They would show you the same camera multiple times. You would mark it? They would remove the mark. You would take some crucial part with you (the lens?)? They would look for other cameras with same lens, maybe already broken ones. You could probably establish some working system but people are not stupid and they would try to game the system.
I was joking about building cameras.
But in reality you would face similar issues. How would people prove they destroy a camera? Show it to you? They would show you the same camera multiple times. You would mark it? They would remove the mark. You would take some crucial part with you (the lens?)? They would look for other cameras with same lens, maybe already broken ones. You could probably establish some working system but people are not stupid and they would try to game the system.