"Have you tried calling his office and " Careful there, witnesses can mean countercharges like slander and a sticky mess.
As we gentlemen say in the sport of yacht racing, "Leave no survivors and you'll spend less time in the protest room." (Who me, say that?!)
Besides, it would be more fun to burn his house down and then stop by to ask if his boat was his only remaining asset. (While lighting up your cheap cigar with a big Zippo, and flicking embers around.) Hey, accidents happen.
(Remember, arson is considered outrageous and just shouldn't be done by unlicensed personnel.)