HOW LONG DOES SOMEBODY NEEDS TO LIVE ON PROPERTY BEFORE CLAIMING IT?

What you are asking about is known as adverse possession. 

The term "adverse possession", sometimes referred to as "squatter's rights", is a legal doctrine providing that if certain requirements are met, someone can legally take another's property without paying for it.

The legal requirements for a claim of adverse possession in KY are:

1. Actual - The adverse possessor (the person now claiming the property) must have had actual physical control over their property.

2. Open & Notorious - The adverse possessor must have engaged in acts of possession in a manner which was capable of being seen and consistent with being a property owner. It may be possible to claim adverse possession of a vacation property on the basis of use only during the vacation season, or to claim adverse possession of a vacant parcel of land by engaging in typical acts of maintenance on the property.

3. Exclusive - The adverse possessor does not occupy the land concurrent with the owner of record or share possession in common with the public. Someone does not have to exclude others from the land in order to claim "exclusive" use, but during the "statutory period" (see below) the person claiming title by adverse possession must have been the only person to treat the land in the manner of an owner.

4. Hostile - Hostility exists where someone possesses the land of another intending to hold to a particular recognizable boundary, regardless of the true boundary line. That is, possession is "hostile" to the title owner's interest in the property. You cannot claim "adverse possession" if you are engaged in the permissive use of somebody else's land.

5. Continuous and Uninterrupted - All elements of adverse possession must be met at all times through the statutory period in order for a claim to be successful. It may be possible to claim adverse possession even if there is a transfer of ownership through the principle of "tacking". For example, a former owner's 4 years of adverse possession can be "tacked" to the present owner's 6 years, for a cumulative 10 years of adverse possession. In KY the statutory period, that is the duration of such possession, is 7 years for land held under color of title (see below), and 15 years for all other claims.

6. Color of Title - A claim to title by adverse possession often must be made under color of title. Color of title means a claim to title by way of a fact which, although on its face appears to support a person’s claim to title, is in some way defective and falls short of actually establishing title to the real estate. An example of a claim made under color of title would be a deed whose execution was defective or is in question. Another common example is where 2 or more persons have received separate deeds to the same parcel of real estate.

At this point you should consult directly with a real estate attorney in your area as to the specific of your particular case.