It is a truth universally acknowledged that a family in possession of a suddenly valuable house is in want of advice.

The same goes for renters who have been warily watching home prices zoom into the stratosphere. They want to know what to do, too.

Whether you already own a house or want to own one, you're probably wondering:

• whether your real estate market is in a bubble;
• whether it was in a bubble that has burst;
• whether a bubble is about to start inflating in your area;
• or why the bubble passed your town by.

Furthermore, being a practical person, you're asking yourself (regardless of the strength or weakness of your neighborhood real-estate market): What's in it for me? How can I work things to my advantage?

You have come to the right place for the answers to these deceptively complex questions. The articles in this real estate guide will advise you what to do in a changing market, whether you're a seller or a buyer.

This guide is informative, but not dull. First comes a look at what $400,000 will buy in 24 cities. Wait till you compare the house 400 grand buys in Fort Wayne, Ind., versus the condo it buys in Miami, Fla.

Dealing with a changing market
Maybe you've lived in your home for a few years and its value has zoomed. Congratulations. You've made money on paper. But if you sell, you might not be able to afford another house in the same market. Has your home become a prison?

What if you want to sell your home, but sales have cooled and it's turning into a buyer's market? There are ways to make your home stand out from the crowd.

A real pro can make money whether home prices are going up or down. Here are ways to profit in a changing real estate environment.

Which direction are interest rates headed this year? Greg McBride makes predictions.

Moves to make
It might be time to rethink your mortgage. A lot of homeowners will bail out of their adjustable-rate mortgages over the next two years.

Whether you're buying or selling a home, Bankrate real-estate advice columnist Steve McLinden has a list of 10 mistakes to avoid.

A lot of agents will tell you that you shouldn't make insultingly low offers. Yeah, well, the market is shifting in favor of buyers in some places, and that means it's time to brush up on the old negotiating tactic of making a lowball offer. Or, better, yet, making several lowball offers, as Joanna Glasner explains.

Don't want to be on the bad side of a lowball offer? Protect yourself from a housing bubble: Be careful about how deeply you go into debt, and don't buy your residence primarily as an investment.

Some homeowners decide to get out while the getting is good. They cash out and collect their money before home prices fall.

But what do you do after you sell your house near what you hope is the top of the market? Go west -- Midwest, that is.

And we give you guidelines of what to do, depending whether your area is about to pop, still inflating, or not in a bubble at all.