He wanted to see bills she had received from the two providers. Luckily, she was suspicious and didn't open her door, show him the bills, or give him any information.
Protect yourself from this type of fraud. If someone comes to your door and says he or she is from an energy company and can help you save money on your electric or gas bill, do not open the door--even if they show you their identification from the energy service company (ESCO) that employs them. The companies do exist, but some of their practices are illegal.
If you do open your door to these strangers before you realize what they're planning to do to you, do not show them your Con Ed or National Grid bill. If you do, they might switch your account away from Con Ed or National Grid to their employer without your permission.
Do not sign anything. Call the police to report the person and describe her or him to the police, if you're able to. If the person touches you or curses at you, tell the police.
Representatives of various energy service companies have gone to homes in this area over the years. Numerous complaints have been filed with the Better Business Bureau against these companies. The Better Business Bureau explains that
Complainants allege they were subject to misleading sales practices, such as unauthorized enrollment in the program offered, and/or misrepresentation of contract length, and/or guarantees of savings, and/or ability to cancel the contract after the initial three day period.
Consumer complaints also allege that the sales representatives [are] misrepresenting their identities.
Additional complaints allege that consumers who did not speak and/or understand English were likewise solicited and their signatures were obtained, enrolling them into a five year contract, despite these individuals' failure to fully understand what they were signing.
Other complaints allege that upon signing up with the company on the premise of savings on gas, consumers' bills did not decrease, but instead increased substantially.
Put yourself in control of your energy accounts now. Whether or not you've been scammed or slammed, contact your utility company (or companies) and state that you want an "ESCO freeze" placed on your accounts.
Any changes made to your account have to originate from you, not from a third-party ESCO. The utility company (Con Ed, National Grid, etc.) will be breaking the law if it makes any changes without your authorization, either on the phone or in writing.