Everyone wants to know how much longer, and how much further, home prices will drop.

The numbers come fast and furious, but they're often contradictory. In one recent week, headlines whipsawed from "Prices falling more slowly" to "Prices falling more sharply."

Here's what we can say:

• On average, prices fell 26% from their 2006 peak through first quarter of 2009. (Home values are down almost twice that in hard-hit cities such as Miami and Sacramento. They're actually up a bit in some areas that weren't swept up in the bubble such as Syracuse, N.Y., and Oklahoma City.)
• They'll fall another 15% to 20% during 2009, according to a rough consensus of economists and real estate experts.
• Prices will bottom out sometime late this year or early 2010, according to those same economists and experts.

So what's a consumer to do?

If you're thinking about buying: Go ahead and take the plunge, but only if you plan to stay in your home for five to 10 years.

Mortgage rates are expected to remain low, at least through the first half of the year, and homes are more affordable than they have been in years.

The value of the house might erode a bit more before the bottom comes, and prices are expected to recover very slowly, but if you're in it for the long haul, you won't be sorry.

To get the best deal, look for houses that have been on the market for several months, and then drive a hard bargain. You can offer as much as 15% below the asking price; the seller doesn't have to accept, but it gives you a starting point.

To get the best deal on a mortgage, work on getting your credit score up and cobbling together the biggest down payment you can afford.

If you're thinking about selling: Wait until next year, if you can. Your home likely will sell more quickly (or at least less slowly) and for a better price.

If you need to try to sell this year, your home could sit on the market for months and you won't get as much for it as you hoped.

Our advice on how to sell in a tough market can help you price and market a home more successfully.

If you own and don't plan to make any changes: Keep an eye on the value of your home but don't obsess about it.

Look into challenging your property tax assessment. In many places, if your home's value falls by 15% or more, it's easy to win an adjustment that will lower your tax bill.

The most exhaustive data are compiled by the National Association of Realtors, which follows median home prices in 150 markets.

Its latest report showed the median price of a single-family home -- the price at which half the homes sold for more and half sold for less -- fell 13.8% from the first quarter of 2008 to $169,000 in the first quarter of 2009.

The worst performance was in Cape Coral-Ft. Myers, Fla., where median prices fell 59.1% to $87,300. Many cities in Florida and California weren't far behind.

Seventy-six cities in all saw prices drop more than 10%. With prices in Anaheim, Los Angeles, San Francisco, Las Vegas, Miami and Orlando losing in excess of 30%.

(Here's where to find out how the median sales price in your town has changed over the last year.)

A bottom in the market -- any market -- is never clear until after a recovery begins. But when a turnaround is in the offing, there should be some signs, including:

• Less inventory. Nothing has hurt home values more than the record number of foreclosures and other distressed properties flooding the market. If we see 4 million or more homes on the market this spring and summer, that's too many.
• Stronger sales. Start paying attention when monthly home sales return to an annualized rate of 5.5 million or more.
• A lower price-to-rent ratio. Watch the relationship between what it costs to buy a house and what it costs to rent an apartment. Moody's Economy.com recently ran these numbers for Time magazine and came up with an average price-to-rent ratio of 19.8 for 54 metro areas. That's down from a peak of 24.4 in 2006, and the closer the ratio comes to the 15-year average of 17.7, the more likely it is that home prices will stabilize.
• A turnaround in the job market. The recession continues to worsen. As long as the economy is losing half-a-million jobs a month and more, we'll see more families losing their homes and foreclosures driving down property values. When the job market starts to firm up, the housing market shouldn't be far behind.
• The Case-Schiller Home Price Index. This is not as extensive as the Realtors' home price survey, covering just the 20 largest markets. But it was the first set of data to spot the peak in prices in 2006. It should also be the first to spot the low point.

By Mary Yanni

Interest.com Contributing Editor