A bad first impression can dissuade a potential buyer. Don't show your property until it's all fixed up. You do not want to give buyers the chance to use the negative first impression they have as means of negotiation.
Ask around for the opinions others have of your home. Real estate agents who see houses everyday can give solid advice on what needs to be done. Consider what architects or landscape designers have to say. What you need are objective opinions, and it's sometimes hard to separate the personal and emotional ties you have for the home from the property itself.
Typically, there are some general fix ups that need to be done both outside and on the inside. As a seller, you should consider the following:
*Landscaping - Has the front yard been maintained? Are areas of the house visible to the street in good condition?
*Cleaning or Redoing the driveway - Is your driveway cluttered with toys, tools, trash etc.?
*Painting - Does both the exterior and the interior look like they have been well taken care of?
*Carpeting - Does the carpet have stains? Or does the carpet look old and dirty?