No. 3: Balancing the spouse's career

Frequent relocations make it challenging for an officer's spouse to hold down a job. "A lot of military spouses end up having a series of short-term jobs, but dual military couples are on the rise," Nordman says. "If the other spouse stays in the service or in the Reserve, that gives you more than one stream of income."

Because military assignments are unpredictable, Hull suggests budgeting for a single income. "That way, any spousal income that you get is extra money that you can throw to debt planning or retirement," he says, adding that the spouse could try getting into the Department of Defense employment system or find nontraditional work that's less dependent on location.

"If you're going overseas, can you teach English as a second language? Can you do crafts? Or consult? Find something that you can do really well where you can create a niche."

Military spouses may also qualify for tuition assistance through the Military Spouse Advancement Accounts program.

No. 4: Getting the right financial advice

Rob Drury, the executive director of the Association of Christian Financial Advisors and a former Air Force major, says service members can have a hard time getting objective financial advice. "It's not a culture that allows for financial planning personnel, so there are a lot of restrictions," he says. 

Some service members fall prey to high-pressure sales tactics for "special mutual funds" or other products. "Don't get sucked into a high-commission financial product just because your command major is selling it," warns Hull. "There are companies that hire military members that just got out of the service to go back and sell products to the old units, and they don't serve the buyer well."

Nordman agrees, adding, "It's tough to find a good financial adviser who understands military issues. They may not understand how a military pension works or how your pay in the military is structured -- how your situation is different from someone who's contributing to a 401k."

No. 5: Transitioning to civilian life

While some service members like Nordman retire after serving 20 years, not everyone can afford early retirement. "The vast majority of people who try to retire with a military pension do not, usually for reasons beyond their control and beyond performance," says Drury. "Defense is not a growth industry. There simply isn't the room for advancement that there once was."

Hull says those planning to pursue a second career in the civilian world should receive as much education as possible through the military assistance program. "If you went into the military straight out of high school, it's a great way to get your bachelor's degree paying very little money out of pocket," he says. "It helps you in your promotion boards and helps you in the civilian world. But remember, you're in college to translate military skills into marketable skills. It's OK to have fun and let loose, but do it in moderation."

In addition to letting loose, some people are tempted to overspend on their higher salaries. Says Rosenthal: "Most military people end up saving a lot of money in their second career when they're able to make more money in the private sector, but it's important that they spend less than they bring in each month."

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