Most home buyers need a down payment of 3.5% to 20% of the purchase price to qualify for a mortgage.

A few can still get away with putting no money down through one type of government-guaranteed loan.

A few may have to come up with more than 20% to buy very expensive homes or condos in overbuilt markets burdened with foreclosures such as Miami.

But the majority of buyers will fall somewhere in between the extremes -- and that's good.

A down payment ensures you have some equity in your home -- that's the difference between what your home is worth and how much you owe on the mortgage.

Far too many borrowers who bought their homes with no down payments during the real estate bubble are now underwater, owing more on their mortgages than their homes are worth.

They can't sell. They can't refinance. And they're defaulting by the hundreds of thousands.

Although lenders are fussier today, the clock hasn't turned back 20 or 30 years to when lenders demanded 20% down payments from everyone.

Here's what you have to do to get a loan with:

No down payment.

There's only one way to get 100% financing for a home today, qualify for a VA loan.

Veterans, including members of the National Guard and reserve units, soldiers on active duty and widows whose spouses' deaths were war-related, are all eligible for these government-guaranteed mortgages.

The Department of Veterans Affairs repays the bank if borrowers default, making these loans cheaper and easier to obtain.

VA loans have the most lenient requirements for income and credit score of almost any type of mortgage. The government doesn't set minimums, but lenders could accept credit scores as low as 580 and debt-to-income ratios as high as 41% of pretax income.

Even a bankruptcy doesn't disqualify you from a VA loan, as long as the bankruptcy occurred at least two years ago and you've been paying on time since then.

In addition, VA loans don't require mortgage insurance for down payments less than 20%.

Instead, VA loans charge a one-time funding fee, which you can roll into your mortgage instead of paying in cash. If you're purchasing your first home and putting no money down, you'll pay 2.15% of the loan amount.

The funding fee is usually waived for widows and vets with service-related disabilities.

A 3.5% down payment.

For a conventional loan on a single-family home, everything has to be just right. You have to have the right property in the right neighborhood. And all aspects of your borrower profile (credit score, income, assets, debt ratios) have to be top-notch.

Obtaining an FHA loan is another way to snag a loan with a low down payment. (The minimum down payment for FHA loans increased from 3.0% to 3.5% on Jan. 1, 2009.)

The Federal Housing Administration was created to help first-time buyers, especially low-to-moderate-income families and minorities. The federal government guarantees repayment, so the lender won't lose money even if you default on your loan.

Qualifying for an FHA loan is easier than for a conventional home loan. A less-than-perfect credit score (but no less than 580) or higher levels of debt don't take you out of the running.

The trade-off is that you'll pay a slightly higher interest rate -- an additional one-eighth to one-quarter percentage point in most cases.

A 10% down payment.

Don't buy a condo. Lenders require at least 10% down on condos, no matter where they are. And fees are higher, too.

In a declining market, lenders typically require an additional 5% down on any property. So, even lenders that accept 5% down will ask for 10% down in areas suffering from high foreclosure rates and the steepest price drops.

California, Nevada, Arizona, Florida, Michigan and Ohio are particularly hard-hit, but dozens of states have pockets of problem areas.

A 20% down payment.

Between 10% and 20%, you simply have to shop around to find a lender who will approve your loan, given the home you're purchasing and your credentials as a borrower.

With a credit score of 740 or higher, you have every advantage -- lower mortgage rates, lower fees and more lenders likely to loan money to you. A credit score of 700 is typically the cutoff for getting a low down payment.

At 680, you'll have to have a minimum of 20% down and pay an additional 1.5% in fees. You'll also need additional assets, such as a retirement fund, taxable investment account, or hefty savings account.

A down payment of more than 20%.

Buying a condo in a declining market is a double whammy. You'll need more than 20% down. Sometimes, a lot more. Lenders require 25% to as much as 50% down, depending on the city.

Jumbo loans are those that are too big to be bought by the two, government-owned companies that provide most of the money for home loans in this country.

Fannie Mae (the Federal National Mortgage Association) and Freddie Mac (the Federal Home Loan Mortgage Corp.) are prohibited from buying loans larger than $729,750 in high-cost areas like New York and San Francisco and much less in most other markets.

That means banks must fund those loans out of their own money or sell them to private investors who demand higher down payments, usually 25% or more.

Some help exists for low-to-moderate-income homeowners who will have the most trouble saving for a down payment.

Congress recently ended the private down payment assistance programs you may have heard about, because too many borrowers who took advantage of them were defaulting on their loans.

But state-sponsored mortgage programs are still an option for those who can meet the strict limits on how much applicants can earn and spend on a home.

By Bonnie Biafore

Interest.com Contributing Editor