I think that’s it, especially if it’s in like that all day. If she’s in an apartment anything like mine the heat from the neighbors on all sides seeps in. 2 bed mill style with poor insulation but keeps my apartment at 65 without having to turn my heat on. If my heats on at 68 for a full month my bill would be around 4-500.

Check to make sure she didn’t accidentally sign up for renewable sourced energy, they quote me 2x+ for the same service as well

I'm surprised their bill wasn't higher. They should be happy to have such good insulation.

It really depends on the unit / construction. Our 2nd floor apartment is 1000sqft with natural gas heat, newer construction, newer windows, energy efficient appliances, etc. We literally leave the thermostat at 72 all year round. Never had a bill over $200 in summer or winter. We stay quite insulated.

Our previous place was on the top-floor of creaky triple-decker with old-ass appliances, drafty windows, etc. It was a downright struggle to keep it at 68. It seemed like the heat would blast non-stop and it was still cold.