General Interior Preparation
Painting: When it comes to preparing a house, painting gives you the best return for money spent. Which rooms should you paint? Any that have dirty or marked walls or any rooms that are currently painted in dark colors. Keep it neutral-off white or antique white is the best.
Carpeting: At the very least, all carpeting needs to be steam cleaned. Any worn, stained or foul smelling carpet should be replaced. You may be tempted to give a "carpet allowance" and that may work. Just remember, most buyers do not have vision.
Operation: If you are not having a whole house inspection done, check all faucets, toilets, and electrical items for correct operation.
Safety: Make sure that your house is safe. Not only can a wobbly railing stop a sale, it could also cause an injury to a potential buyer who is not familiar with your house (and is spending time looking instead of being careful).
Clutter: If an item is not necessary for your day-to-day life, box it up and store it or throw it out!
Fireplace: Have a professional fireplace or woodstove cleaning and inspection. The buyer will most likely request it anyhow. Getting it done in advance impresses the buyer and makes the home appear cleaner and fresher smelling.
Closets: Make sure all closets are neat, clean, and organized. See above item on clutter.
Doors and Windows: Check all for smooth operation. Replace any cracked window panes.
Cleaning: Even though you may consider your house clean and tidy, a thorough cleaning--including dusting, washing, and waxing everything--will always make a house more appealing.
REMEMBER that they are not able to look at a room that needs paint and carpet and imagine it fresh and attractive. Telling them that something will be cleaned, or painted, or repaired may work with some, but the majority will not be able to envision the house after the changes have been made and will scratch your house from their list.
Preparing Your House--Interior
Many home sellers make the mistake of ignoring certain repair or maintenance items in the hope that a potential buyer will either not notice, or if they do, telling them that they (the seller) will repair or replace the item. Most buyers do not have vision.