Fake caller ID - TELEMARKETER SPAM
Do not do business with these criminals. If they can't be honest about calling numbers on the DoNotCallList, then WHY WOULD YOU EVER LET THEM IN YOUR HOME?
They either are marketing for their own company, or likely they sell the lead to a contractor. The contractor either knows about it or not.
I usually tell them about a "dream" project so they will make an appointment. When they call back to make the appointment, I tell them I'm on the other line and can I get a number to call them back (now that they are catching on to me, they sometimes call from blocked numbers to confirm the appointment)
I then confirm the number is valid and report it to the FTC Do Not Call list at www.DoNotCall.gov