A foreclosure is always a scary situation for a homeowner, but the spooky factor is ramped up by the nicknames for some of these circumstances.

When a property is foreclosed but the owner remains on the premises, it is known as a "vampire foreclosure." If a foreclosed home starts to deteriorate due to lack of maintenance, it goes by the name of a "zombie foreclosure."

Either case can be pretty frightening for a neighborhood or the real estate market. While foreclosed listings are sometimes attractive to buyers because of the option to purchase an investment property or acquire a home at a bargain price, vampire and zombie foreclosures can have a much more detrimental effect on the market.

VAMPIRE FORECLOSURES

In most cases, a homeowner decides to move out of a property once it is foreclosed. In a vampire foreclosure, they decide to stay put during the process.

Amy Loftsgordon, a contributing editor for the legal site Nolo, says this can have a detrimental effect on the market. A bank will not be able to list the home for sale if it is occupied.

By keeping such properties off the market, the housing inventory goes down and sales prices on available homes go up. Loftsgordon says this actually helps improve home values in the short term.

However, the rising sales prices can also provide an incentive for banks to bring out the garlic and crosses against vampire foreclosures. Once they feel they can get a good price for the property, a bank will pursue eviction of the homeowner and put the property on the market.

Loftsgordon says that once vampire foreclosures start to appear in significant numbers, they will stall the increase in sales prices and home values. She says this pattern will be especially noticeable in neighborhoods with high concentrations of vampire foreclosures.

A report by the real estate information site RealtyTrac estimates that 47 percent of bank-owned properties are vampire foreclosures. Judy Martel, writing for Bankrate, says vampire foreclosures are particularly prevalent in some regions. The estimated percentage is 72 percent in Virginia and 65 percent in Houston, Texas.

Martel says RealtyTrac vice president Daren Blomquist estimated that vampire foreclosures would start to hit the market in time for Halloween. In the October 2013 article, Blomquist estimated that the properties would begin showing up a year later.

ZOMBIE FORECLOSURES

Some vampire foreclosures may occur because a homeowner doesn't want to be the victim of a zombie foreclosure. In these cases, a stalled foreclosure can unexpectedly burden the homeowner with unexpected costs even after they've left the property.

Homeowners often leave a foreclosed property in anticipation of it being sold at auction, transferred to another owner, or repossessed by the bank. But in some cases, this process never happens.

If the bank has too many foreclosed properties to manage, doesn't consider the property to be worth the expense of completing a foreclosure, or otherwise decides against moving forward with the process, the property never changes hands. When this occurs, the homeowner will have moved out of the property without realizing that they still hold the title.

Since the bank does not take any part in maintaining a zombie foreclosure, the property is likely to become dilapidated. Lawns and shrubs grow out of control, and leaks and other damage go unrepaired. These properties can also become targets for vandalism or squatters. All of these factors help drive down the property values in the neighborhood as a whole.

Loftsgordon says the homeowner might only discover that they still own the property when they are hit with accrued bills and other penalties related to the zombie foreclosure. These can include unpaid property taxes, fines for failure to comply with housing codes, and even municipal fees for cleaning up or demolishing the home.

Martel says about 20 percent of the foreclosures in the United States are thought to be zombified.

Amy Fontinelle, writing for Investopedia, says homeowners should ensure that the foreclosure process is completed before moving out. She says a homeowner can also work with the bank to try to find an agreeable arrangement such as a loan modification or short sale.

Loftsgordon says a homeowner can confirm that a deed has been transferred by checking local property records.