A low-ball offer is a term used to describe an offer on a house that is substantially less than the asking price. While any offer can be presented, a low-ball offer can sour a prospective sale and discourage the seller from negotiating at all. Unless the house is very overpriced, the offer will probably be rejected. In a buyer's market a motivated seller will either accept or make a counter-offer.
Turn off the lights in any room you’re not using, or consider installing timers, photo cells, or occupancy sensors to reduce the amount of time your lights are on.