Before a potential homebuyer can get to your house, he has to drive past your neighbors, and they can take a bite out of your home's value in a multitude of ways. For example, arguing over exactly which blades of grass encompass the all-important property line is just one of the many disagreements that can sour neighbors against one another. Sometimes those arguments spill over to future owners. If it's apparent you have a dispute with the folks next door, many buyers may pass or offer a lower price.
Another issue that can crop up is colorblindness -- your neighbor's colorblindness. If you're one of those unlucky people who have a poorly pigmented house in your neighborhood, it's doing more than giving you something to grumble about when you pass it on your morning jog. That eyesore is driving potential buyers -- and potential dollars -- away as well.
Buyers may also consider a nearby unkempt lawn or annoying pet within earshot as strikes against a property. People who party at all hours can be a problem, too, as can living close to a registered sex offender. If you're within a tenth of a mile, that will almost certainly take away some of your property value and your home will likely take much longer to sell -- to the tune of about 9 percent of the value and 10 percent more time on the market [sources: O'Connell, Longwood University].
Unfortunately, there isn't a lot you can do when items like these are an issue besides potentially performing some figurative fence mending (or abject pleading) with your neighbors. You can do something about your own property though. Let's talk curb appeal next.