Check all the ceilings for water stains, whether the leak is caused by plumbing or a faulty roof. Find the leak and repair it and make sure a proper job is done. Nothing irritates a buyer more than finding out - after the fact - about plumbing or roofing leaks. They will be talking about calling a lawyer faster than your car engine starts when you turn the ignition key.
If a water stain is left after something you have already repaired, do the cosmetic work necessary to improve the desirability of your home. That means painting.
You may have to paint anyway, especially if dirt has accumulated in spots or you have an outdated color scheme. Painting makes a home look fresh and new on the inside and never fails to impress.
Painting can be your best investment when selling your home. It is not a very expensive operation and often you can do it yourself. Do not choose colors based on your own preferences, but based on what would appeal to the widest possible number of buyers. You should almost always choose an off-white color because white helps your rooms appear bright and spacious.
Carpet and Flooring
Unless your carpet appears old and worn, or it is definitely an outdated style or color, you probably should do nothing more than hire a good carpet cleaner. If you do choose to replace it, do so with something inexpensive in a fairly neutral color.
Repair or replace broken floor tiles, but do not spend a lot of money on anything. Remember, you are not fixing up the place for yourself. You want to move. Your goal is simply to have few negative impressions upon those who may want to purchase your property.