How do you know whether you're getting a good deal on a house?

Here's a hint: if the real estate agent suggests that she's willing to pay you to take the house off her hands…you may be dealing with a lemon.

Unfortunately, it's rarely that obvious. So how can you be sure that you're not going to get stuck with a terrible house that makes you feel you're in the latest Paranormal Activity?

Inspector, Inspector

One way is to hire a house inspector. A professional inspection gets everything in writing, so if there's an infestation of ants, ghosts in the attic, or bats floating around the basement, you'll know about it—and you can use that information to either walk away from the deal or to talk down the price of the home.

Without an inspection, you have no idea what's happening behind the walls. And if the lime green paint is anything to go by, a whole lot might be going on back there.

Two Quick and Dirty Ways to Estimate House Value

An inspection comes once you're basically ready to buy the house. But what if you're at an earlier stage in the process? Like you're just driving through neighborhoods and seeing what's out there?

1. One way of guesstimating the value or price of a home is by using the "replacement cost" value. Determine the cost of the land and permits and figure out how much it would cost to build the same house from scratch (using contractors and today's prices on the materials).
2. Since that's kind of hard to do if you're not a construction worker and don't know the price of land, another option is to (legally) stalk the other houses in the same neighborhood. Check out what houses have sold in the same neighborhood in the last six months. What did they sell for? (Hint: real estate websites sometimes have this information, and so do realtors). The house you're looking for probably falls somewhere in the same range.

The one exception: truly unique homes. If the home you're looking for has seven-foot mounted statues of Brad Pitt in every room and no kitchen or bedrooms, that house is probably worth less than its neighbors; after all, many buyers want outrageous stuff like normal rooms and a place to cook their food without statues nearby. (We're not sure why.) Since fewer people are willing to buy, the house is priced lower.

And, hey, even if Brad statues are your cup of tea, be smart with your cash: pay attention to location and whether other buyers would love the house, too. You may want to sell someday and it'll be nice if some interested folks show up to eat your realtor's tiny sandwiches at the open house when the time comes.