Image: Woman counting money © Jose Luis Pelaez Inc, Blend Images, Getty Images

I'll break this to you gently: You're probably not going to end up filthy rich.

Only about 80,000 U.S. households (out of 115 million) qualify as "the glittering rich," which is what author Thomas J. Stanley calls the people with seven-figure incomes and eight-figure wealth. (Stanley co-authored the classic money book "The Millionaire Next Door" and authored "Stop Acting Rich . . . And Start Living Like a Real Millionaire.")

But you have a pretty good shot at accumulating a substantial net worth over your lifetime, depending on your choices. A relatively small number of factors can make a big difference in your wealth. Such as:

1. Marriage

Two can't live as cheaply as one, but sharing household expenses can have an impressive impact on your wealth.

The median net worth of all married-couple households in a Census Bureau wealth study (.pdf file) was more than four times higher than that of single men and five times higher than single women.

Liz Weston

Liz Weston

You'd expect some disparity, since most people marry eventually, meaning the group of single people would skew younger and poorer.

But the wealth gap remains substantial even when you look at people the same age. A 15-year study of 9,000 people, starting in their 20s, found that people who married and stayed married built up nearly twice the net worth of people who stayed single.

Furthermore, married couples' wealth increased at a faster pace -- an average of 16% a year, compared with 8% for single people. That suggests that couples who stay together will build substantially more wealth over their lifetimes than two comparable singles.

But what marriage gives, divorce can take away -- and then some. Four years before a divorce, wealth typically starts to decline. After the final breakup, the typical divorced person's net worth is 77% less than that of the typical person who remained single.

"While men come out slightly ahead, divorce destroys wealth dramatically for both sexes," wrote Jay Zagorsky, a researcher for Ohio State University's Center for Human Resource Research. "Becoming and staying married is associated with higher net worth than being single or divorced."

The takeaway: Marry, but marry smart. Spending money on marriage counseling can be an investment if it helps prevent divorce. Read "Get real: Marriage is a business."

2. Homeownership

Owning a home is clearly associated with higher net worth. But as with marriage, a bad ending can be devastating to your finances.

Homeowners had a median net worth of $234,200 in 2007, the latest available Survey of Consumer Finances from the Federal Reserve says. Renters' median net worth was $5,100, or just 2% that of homeowners.

As millions of people have discovered since 2006, however, a house you can't afford isn't an asset. Trying to make unaffordable mortgage payments can drain your savings, while a foreclosure or short sale can substantially lower your credit scores with an effect that lasts up to seven years.

Research on people's net worth after a foreclosure is scarce, but Zagorsky and colleague Lois R. Lupica of the University of Maine School of Law found that the fallout from a similar traumatic setback -- bankruptcy -- was surprisingly long-lived. Those who filed for bankruptcy typically took more than 25 years to "catch up" to the net worth accumulated by those who hadn't filed. Fifteen years after their filing, for example, the median net worth of those who'd filed for bankruptcy was $132,772, compared with $192,251 for those who hadn't.

The takeaway: Most U.S. households (65.9% at last count) own their own homes, but it's not a slam-dunk decision. Make sure you're ready to stay put for several years. You also should have enough saved so you have some money after closing to cover the continuing costs of maintenance and repairs. Finally, try to keep your mortgage payments to 25% or less of your gross income. That can help ensure you have enough money left over to save for other goals and to live your life. Remember, you want to own your home -- not be owned by it. For more, read "Are you crazy to buy a home now?"

3. A college education

College doesn't always pay off financially. In the U.S., one out of five men and one of seven women who have college degrees earn less than their counterparts with just a high school diploma. The worst off are the ones who take on huge amounts of debt and either never get their degrees or get degrees in fields with poor job prospects.

But for the vast majority of college graduates, a degree makes a huge difference. Their median household income was $78,200, while households headed by those with only a high school diploma earned $36,700. The Pew Research Center estimates that, after factoring in the costs of college and earnings forgone during those years, the typical college graduate earns $550,000 more than the typical high school graduate over a lifetime.

Household wealth for U.S. college graduates is significantly higher, as well.

GRAPH HERE

Furthermore, unemployment rates for college graduates are half of what they are for people with only high school diplomas.

The takeaway: A college degree is important. It will become more so in the future as well-paying manufacturing and union jobs disappear. But it matters what you study and how much you pay for that education. College students and their families need to make sure they're studying for fields that have good job opportunities. Plus, they have to make sure they don't overdose on loans. Read "Should your kid skip college?" for more.

4. Self-employment

You've heard scary statistics about how many small businesses fail -- statistics that are usually exaggerated, by the way.

Create the right business, though, and the upside is all yours. The self-employed not only earn more (their household median income was $75,700 in 2007, compared with $56,600 for employees), but they accumulate dramatically more. The median household net worth of entrepreneurs was $388,700, compared with $93,200 for households whose head worked for somebody else.

But what about that high failure rate? You may have heard that anywhere from half to 90% of small businesses fail in the first year, but that isn't supported by research. When a small business employs at least one person besides the owner, 70% survive at least two years, half are still around five years later and a quarter stay in business 15 years or more, according to the Small Business Administration. And the "dropouts" aren't necessarily failures. Businesses can be shut down or sold for a number of reasons, including a serial entrepreneur who's moving on to something else.

Annually, about 10% of employer businesses close for various reasons. The turnover rate for owner-only businesses is harder to track, but the SBA estimates it's about three times higher since it's easier to open and shut a shop when you don't have employees.

Now consider the "failure" rate when you're working for others. Even among older, more stable workers -- those aged 39 to 44 -- one-third of the jobs they got ended in less than a year, and 68% ended in less than five years, according to a study by the Bureau of Labor Statistics.

The takeaway: Entrepreneurship, like marriage or homeownership, isn't for everyone. But if you have a desire to run your own show, you shouldn't let other people's failures hold you back. You can find plenty of free and low-cost help in starting a business from the SBA, including the small-business development centers located in many cities, and from SCORE, a nonprofit educational group that connects small-business owners with experienced mentors.

5. Choosing to save

Are you convinced the reason you can't save is that you don't make enough money? You're probably deluding yourself.

Income differences don't explain why some households accumulate wealth and some don't. Ivy League researchers Steven F. Venti and David A. Wise found that some high-income people wind up with little wealth and that some low-income people accumulate a lot.

A study of 3,992 households whose heads were near retirement age found income differences explained just 5% of the variations in wealth. Life events such as inheritances, big medical bills, divorce and the number of children accounted for just 4%. Investment choices accounted for 8%.

So what made the most difference? How much the households chose to save. Even some of the lowest-income households managed to accumulate significant wealth.

Click here to become a fan of MSN Money on Facebook

The takeaway. Making savings a priority, and paying yourself first from every check you get, turns out to be the No. 1 way to build wealth. So get started. For more, read Trent Hamm's wonderful post "12 excuses for being broke."

Liz Weston is the Web's most-read personal-finance writer. She is the author of several books, most recently "The 10 Commandments of Money: Survive and Thrive in the New Economy" (find it on Bing). Weston's award-winning columns appear every Monday and Thursday, exclusively on MSN Money. Join the conversation and send in your financial questions on Liz Weston's Facebook fan page.