When asked for a location - very vague response. Refuses to give out a California Contractor's License number - etc., etc., more reasons not to do business with them.
Basically they are a call center who get paid to make appointments for client contractors in your area - that's why they can't give you a state license number - they don't have one.
The numbers they call from are cell phones, probably personal ones, that's why they are always different.
If they do give you a location, it's like "we have offices all over Southern California" - well give me one of them, and they'll hang up.
I refuse to do business with a contractor who has to use telephone soliciting and who is not located within 20 miles of my house. If there's a problem, you'll hear "well we can't get to (your city) until some time next week, etc., etc. - just either don't answer the call or hang up when they start their pitch.
Or, if you want to game them, tell them they'll have to call the bank because the house has been repossessed, or tell them you've moved and they'll have to call the new owner, or some other legitimate reason they have wasted their time. Or better yet, tell them you want some work done in six months and ask for their number so you can call them - you won't get one.