Thank you all good people for your replies. You will probably be
shocked to find out that this guy IS a professional roofer or/and
represented a roofing company. I checked their website. A locally owned
family business since 1939! Licensed. Bonded. Insured. A registered
BBB member with one resolved complaint. Well sort of resolved -- the
customer still wasn't satisfied. Also, the company was renamed (why?)
three years ago, so the BBB doesn't have much info on them.

Several of you noted that it would be difficult for me to make him pay
for the damage. Based on the info above, I believe it will be a lot
easier for me to deal with him, will it not?... Unless he says "I
didn't do it"... Is there a way to prove it is a recent damage?

Could someone please explain the "bonded" part? How does this work? We
haven't even signed a contract. He came over for a free estimate, did
the damage and off he went.

Thanks.