Entry way

Clean and polish everything.
Make sure it’s well lit.
Make it clutter free.

Kitchens are under close scrutiny

Clean the exterior of all appliances, including the stove hood filter.
Clean counter tops and cabinet faces, the shiner, the better.

Clutter free

Remove magnets and messages from the front of the refrigerator.
Clean floor, consider new if it is worn.
If you have ceramic tile, make sure the grout is clean, there are whitening products.

Bathrooms are also extremely important

If faucets drip, repair or replace them.
Remove stains from all fixtures.
Make sure all lights have the highest wattage safe for each fixture.
Put out fresh, clean towels.
Check ceramic tile, make sure the grout is clean.
Remove any evidence of mildew.
Make sure drains are clog free.
Shower doors should sparkle.

Bedrooms

Arrange the furniture for the flow of traffic.
Make sure its clutter free.

Living room/Family Room/Den

Arrange the furniture for the flow of traffic, give the illusion of space.
Remove ashes from fireplaces and woodstoves.
Make sure all light switches work.
Clean the drapes
Polish, mop the floors

Storage Areas

Basement, Garage, Attic
Remove all junk and clutter (do you detect a theme?)
If the basement is damp or musty, try a dehumidifier.
Make sure these areas are well lit.