As someone that tried every legitimate way to go about the problem. Everything you wrote is utopic and not what happens. The post master wanted nothing to do with it, the cops wanted nothing to do with it, and let me tell you, the crook has the upper hand 99% of the time, if they want to go that route. Regardless if they are the buyer or seller.
The postmaster took my statement, I showed him the empty case, guy said the cue was in the case when I shipped it. It was a 4 lb package, they didn't care.
Here is how simple it is.. you go to the police, and file a police report. You're the buyer, say.. I sent him his cue and now he is not giving me my money back. They do the report as a favor to YOU. Send the report to Paypal, and they are automatically the victor in the dispute because now its a "legal" proceeding and they don't care at that point.
The seller is naked as a jaybird, all the time. Not sometime, all the time.
JV