There may be a better way, however, for potential buyers to approach the problem. “Predicting interest rates is a whole lot easier than predicting home prices,” says Glenn Kelman, chief executive of Redfin, a multistate discount online real estate brokerage company based in Seattle. “Before you buy the house, you buy the money,” he says.

Image An ad for mortgage rates last year at a bank in Maine. The general direction of interest rates is one thing that a potential homebuyer can often predict. Credit... Robert F. Bukaty/Associated Press

It’s a little like walking into a dealership to buy a car, and finding the saleswoman immediately jotting down what your monthly payments will be and starting the negotiations there. That’s absolutely the wrong way to buy a car. But for a prospective homeowner, it’s a good place to start the analysis to determine how much house you can buy.

Instead of betting on home prices, you make a bet on whether money will become cheaper or more expensive, allowing you to buy more or less house.

That’s where the regular Joe has a pretty good shot of being right. You won’t know day to day, or week to week, what’s happening to rates, and a jolt like a default in Greece or a change in Chinese monetary policy can throw everything off. But, generally, the Federal Reserve is telegraphing where things are headed over the next six months.

“I can’t prove to you that housing prices have definitely bottomed out,” Mr. Kelman says. “I can say with a fair degree of certainty that the cost of money will go higher.”

OF course, if rates go up, home prices tend to dampen. Borrowing $300,000 at 5 percent costs you $1,610 a month. If rates rise to 6 percent, that’s $188 a month more, or $67,680 over 30 years. Would the price of a $375,000 house fall because of a half-point rate hike? Now you are back to guessing about home prices. Don’t go there. Maintain your focus.

“People are frequently buying for the wrong reasons,” says Frank LLosa, a real estate agent working in northern Virginia. In most cases, he says, they think that they are getting an income tax break or that their home is an investment.