With over 35 years of experience in masonry construction and home improvement, I believe I can give you some good tips.
The first, most important thing to do is consider what is known as curb-appeal. If the house needs exterior paint, paint it. And make sure the landscaping looks nice --- grass watered, trees pruned, unstained driveway, etc.
Although most people don't like to hear this one, if your neighbors’ yards look bad, this will also devalue your home. Again, curb-appeal. If you have a neighbor whose yard looks bad, offer to clean it up for him/her. I know, that doesn't sound like much fun, but it can make a big difference in your property value.If a buyer pulls up in front of your home and sees the yard next door is trashed, he/she will likely just keep driving.
Paint the interior if it needs it. If not, make sure the interior is well cleaned. Shampoo the carpets even if they don't need it. It makes the home smell better and that's also very important.
Speaking of smell, before showing the home, put a drop of vanilla extract on the light bulb in the kitchen. Never discount the psychological aspect to selling a home. This trick makes the kitchen seem much more homier and, believe it or not, a wife tends to have a major impact on hubbie's decision whether or not to buy! And you want the wife to feel like it is her kitchen already, as soon as she enters it. Keep in mind that it is nearly impossible to sell a house (except to an investor) but everyone wants to own a home.
Relative to the paragraph above, when showing the home to a potential buyer, NEVER refer to it as a house; ALWAYS refer to it as a home!
These are the quick, easy, and inexpensive ways to improve your chances of selling the home for a good price. Other larger improvements will cost quite a bit more so you have to seriously think about the cost of other improvements and whether or not your return on those costs make them worth doing.
The next most important project in the list is upgrading fixtures in the bathrooms and kitchen. But as I said, be careful that you're not spending more than the likely return.
Next is the garage. If the home does not have an attached garage, adding one can significantly increase the value of the home.
Beyond these things, most other improvements are unlikely to give you a return.