Curtains and drapes should be fresh and attractive. Dust, clean, and scrub everything from attic to basement. Shampoo the carpeting. Open all drapes, pull up shades, and let the light in. Turn off all television sets while the house is being shown.
Soft music is desirable.
Water all dying plants or get rid of them. Put new washers in all dripping faucets. Throw away the torn shower curtain and put up a new one. If you cannot get rid of stains in toilet bowl, buy a new one. This applies to all bathroom, including the one in the basement that is seldom used.