Are you suggesting that police services should operate like a service for hire? It isn't clear to me if you think the victim should hire the police to investigate (and thus decide if their price is lower than re-purchasing the item) or if you think the police are only expected to investigate based on the value of the item.

In either case it doesn't sound like a sound way to operate a police department. It seems like a good way to incentivize vigilantism though.