What Did the Grape Say When the Elephant Stepped on It?
Not much, it just let out a little Wine. Get it?
Ok, it's a groaner, but for some weird reason this joke (the first one I ever memorized and repeated after reading it in the Highlights Magazine at the Dentist's way back in 3rd grade)comes to mind every time I walk through a listing and hit a floor squeak. 
Sometimes I find the squeak first and other times the buyers will find them. The discoverer often will freeze on the spot, and rock back and forth over the squeak repetitively until the other party notices as if to say "Look what I found".
When my boys were teenagers we lived in a two story which had a great squeak at the top of the stairs. No way around that baby if you were trying to sneak downstairs. But when we sold the house, that was on the top of the list of things to repair.
As it has been explained to me, most squeaks arise from a nail having come loose in a joist below the subfloor. As weight is put on the floor it moves up and down along the nail making the squeak. In most situations, it's not a difficult fix. There are several kits available at Home Depot or local hardware stores for eliminating squeaks and creaks under carpets and even under hardwood floors. I've been told the Puyallup Fair has a booth every year with break-away screws for floor squesks too, although I've never seen them. My husband was able to pull the carpet back and drill in some screws to eliminate our floor mounted monitor.
Whether you're a handy do-it-yourself type or just don't have the skills or time to deal with it and call in a handyman, make sure you address floor squeaks prior to listing. You want Buyers viewing your home to focus on the house, not hunting for the next big squeak.
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