All great points below in researching historical bill history on a property, but I want to focus on Ariana's point. Pay particular attention to the type of heating and cooling equipment that a property has. Maryland temps can sway greatly. Heat pumps in cold weather (under 40 degrees) tend to cost more, as well as baseboard heating. Gas is a very efficient form of heating but many of these areas, if they have gas equipment, are using propane. Propane is not nearly as cheap as natural gas piped in from a main source. So, a propane furnace may be quite expensive if you like it warm in the winter. Older homes in this area commonly have oil furnaces or baseboard heating - this would be your most expensive in utility bills. So, just keep that in mind when you are looking.
Best of luck on your move,
Home Towne Real Estate - Owings