They did that to me too. I said give me your number, I'll look into it and if it's for real, I'll get back to you. He says, ok can I come in and we can write it out, and takes a step onto my door frame. I step forward too, stand in his face and calmly say no.
Googled it and turns out they get many people on the hook making it sound like they're just filling out an official inspection form. Your gas company charges you out the butt for breaking the contract and you end up paying more. Direct Energy sent my neighbors and me a letter a week later, saying to watch out for these because once they have your signature, no one can help you.