Two years ago, Caroline Spears was finally living on her own, roommate-free, in a one-bedroom apartment in San Francisco, where the cost of living continues to go up. She was drawn to its affordability and space. “It was a great work-from-home spot,” Spears said. She didn’t foresee, however, the high energy bills that would result from cranking up the gas heater when her apartment would turn into an icebox in the winter.
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