By Morgan Brennan and Michelle Cerone

Forbes.com

By the time Thomas Brennan and Mary Alice Shallow bought their 5,000-square-foot farmhouse from Union State Bank, it had sat abandoned for nine months. At a paltry going price of $275,000, the Putnam County, N.Y. abode was nearly 60% cheaper than the other neighborhood homes, thanks to a foreclosure discount and years of neglect.

The property needed repairs, with some the worst damage having been inflicted by squatters, looters and vandals in the nine months leading up to Brennan and Shallow's purchase.

"The copper plumbing had been stolen out of the house, the windows were busted, the front door broken down," says Brennan. "Kids were inside vandalizing the house, and other people were stealing the antique furniture."

In Pictures: Nine Creepy Abandoned Mansions

Homes across the U.S. sit abandoned, empty and vulnerable to vandalism, due in large part to the ongoing housing crisis. The U.S. Census Bureau reported that the national homeowner vacancy rate for the fourth quarter of 2010 was 2.7%. That represents more than 2 million empty homes--including some mansions.

A quick search on real estate listing sites like Realtor.com and Trulia.com shows thousands of palatial estates deserted and patiently awaiting sale, as pools turn green and dust settles on granite countertops. Some of these abodes belong to owners who have listed the properties and relocated. Many more face foreclosure or are already bank-owned.

"What's different about this foreclosure cycle is it has taken houses out of every aspect of the housing market," explains Rick Sharga, senior vice president at RealtyTrac, an Irvine, Calif., foreclosure listing site. "You rarely saw mansions in foreclosure [until recently], and now you are seeing much more expensive types of properties in foreclosure."

RealtyTrac has seen an unprecedented level of default activity in some of America's ritziest neighborhoods. For example, Beverly Hills, the sixth-most-expensive ZIP code in the country, had a 700% increase in foreclosures of homes $2 million and up over the last three years.

We compiled a list of creepy abandoned mansions. They've all been empty for years. In a few cases, the homes have recently been sold to buyers willing restore them. Some are foreclosures; some the targets of longstanding legal battles; some are still actively owned from afar.

What do we mean by creepy? We confined our search to homes decaying into the ground, boasting spooky legends or tragic murders, or serving as sites for sordid illegal activities. Many of them are for sale: Boxer Mike Tyson's deserted former Southington, Ohio, manor is listed for $1.3 million, and the allegedly haunted New Hampshire castle once inhabited by railroad tycoon Benjamin Ames Kimball can be had for a steeply discounted $880,000.

Unfortunately there is no easy answer for what to do with empty structures, whether they're mansions, more typical single-family residences or unfinished developments.

Here are five of the creepiest, abandoned mansions:

Mudhouse Mansion
4730 Mudhouse Rd., Lancaster, OH
Across the U.S. sprawling estates sit empty and abandoned. Fairfield County’s Mudhouse Mansion is one eerie example. This 19th-century red brick building has not housed a regular occupant since the 1930s, despite having an owner who still pays the property taxes. The once regal structure has fallen victim to fires, vandalism and rumors of ghastly hauntings.

Mudhouse Mansion in Lancaster, OH Photo: Robert Batina

Vacant Mansion
3737 State Route 534, Southington, OH
The vacant manse was home to boxer Mike Tyson in the 1990s. The current asking price is $1.3 million, despite overgrown lawns and a moss-colored pool.

Unsold, abandoned mansion in Lancaster, OH Photo: Realtor.com

Abandoned Lakefront Estate
17920 W Colonial Drive, Oakland, Fla.
Following the Sept. 11, 2001, terror attacks, Khalil bin Laden, Osama's brother, fled this lakefront estate. During six years of vacancy, damage to the property included bullet holes in the walls. More recently acquired, it is currently up for grabs for $2 million.

Former Florida home of Osama Bin Laden's brother is for sale. Photo: ERA real estate

Lynnewood Hall
920 Spring Ave., Elkins Park, Pa.
The sprawling Widener manse, nicknamed "last of the American Versailles," sits empty and decaying as years' worth of legal battles rage on.

Lynnewood Hall in Elkins Park, Pa. Photo: http://sites.google.com/site/lynnewoodhall/home/exterior-photos

Kimball Castle
59 Lockes Hill Rd., Gilford, N.H.
For $880,000 you can investigate whether this eerie hillside castle "in need of total rehab" indeed deserved a cameo on reality TV series Ghost Hunters.

Kimball Castle in Gilford, N.H. Photo: Public Domain

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