Thanks for this specific info BUT You are too kind - or naive. This is not merely a "'nut' who gets off harassing people".
THESE ARE CRIMINAL SCAMMERS who are ATTEMPTING A PHISHING SCAM - meaning posing as Selling something or 'giving' something away for free IN ORDER TO GET PEOPLE'S BANK ACCOUNT OR CREDIT CARD NUMBERS in order to STEAL FROM YOU.
Best NOT TO ANSWER, NOT TO ENGAGE IN CONVERSATION with them. IGNORE by not answering, BLOCK the numbers if you can (ALL ARE 253-382-9XXX) Or, Pick up/Hang up immediately without answering/saying ANYTHING to 'confuse' the robodialer. That SEEMS to help CUT DOWN on the number and frequency of these calls.
I heard recently that someone found out the callers location and went there unexpectedly and when the person answered the door, he was beaten to within an inch of his life.