Daylight and light colors make otherwise small, dark spaces seem larger and more cheerful. Repaint with a fresh coat of white, off-white or neutral color paint. Open the draperies, shades or blinds. If the rooms are cluttered, pack up and store personal items, artwork and non-essential furnishings. Freshen the air.
Unpleasant odors are a big turn off.
Fresh paint and a good cleaning can make the house smell new, but cooking, pet, cigarette and medicinal odors will undo your efforts. Make sure the house is clean each time your real estate agent calls to say a perspective buyer is on the way. Easier yet, boil up a potpourri of pie spices. If your home needs major repairs, measure what their cost will add to the sales price. Your appraiser or broker can advise you on the cost effectiveness of repairs and how good the local market is for fix up properties.