This "contractor" apparently spoofed his caller ID.
I actually talked to the son of the lady who owns this number, last week when these calls started coming in to my 714-897 number.
The son said AT&T told him the calls were originating from various IP addresses on the Internet ("like Skype") and that they could change her number or try putting an announcement on her answering machine to explain that his mother did not call anyone. He said he would try the announcement first.
Hopefully, she doesn't get "black listed" because some jerk randomly picked this phone to make other 714 people answer (like "it's local so maybe it's not a telemarketer").
If it is true that this man calls with wrong 714 number to others in 714 probably robot calls 714-XXX-0000 to 714-XXX-9999. I got call on 714-532-XX17 and 714-532-XX89 with in few minutes. Don't need to be on list.