Are you married with children? You don't just go blowing holes in walls. A dog is a great deterrent. Ask any criminal and they'll tell you outright that it's difficult to negotiate with a dog. Dog, person at home, person at home that may be armed would the best deterrent to any burglar.
Did this guy show up on any mental radars? Sounds like another case where the mother had inside knowledge of issues with her son. A LOT of physiological changes occur in the brain in the late teens/early 20s.