Quoted from pinbum:Tell him to make sure to bring the machine back to Arizona when he comes down. And leave it at that.
^^This^^
In my day job, I get asshats from time to time threatening to "take legal action" against me when I have in fact done nothing wrong. My response is always the same. I politely tell them to take whatever action they deem necessary and to make sure any future correspondence be funneled through our respective lawyers. I then accept no further calls, emails, etc on the matter. I suggest you do the same, and not lose a moments rest over the situation.