Made a few monumental money gaffes? Don't be shy about sharing them with Sheryl Garrett. In her 18 years in the financial planning field, she's seen it all -- the families with significant assets and no wills; the near-retirees with nothing in their nest eggs; the singles whose first homes are four times more than they can afford; the average workers who lost their hard-earned savings to unscrupulous money pros.

Garrett's not timid about confessing her personal financial weak spots, either. "Until my money gets invested, it's not sacred. ... If I have money in my checking account or my savings account, that money is available to be spent," she says.

Her honesty is refreshing -- and so is her professional financial advice. Garrett's accolades are numerous: She's been on Investment Advisor magazine's list of the top 25 most influential people in the financial planning industry and Mutual Funds magazine's list of the top 100 financial advisors.

But instead of building a booming business on the backs of clients of means, she decided that good money advice should be available to all. The service she founded in 2000 -- the Garrett Planning Network -- is made up of 250 personally vetted and coached financial advisors who charge for their services on an hourly, as-needed basis.

Who better to provide a map of the minefield of financial issues faced by the average American? Garrett is the editor of the recently released "On the Road" series of personal finance books about life's major money milestones. Last week, our resident retirement expert Robert Brokamp sat down with Garrett to talk about the problems with big brokerage advice, the most oversold financial products, and the real questions to ask the pros -- even the ones she endorses -- before you take their advice. The full interview, released today, is available to Motley Fool Rule Your Retirement subscribers. (For a free 30-day trial and access to the expert interviews, investment advice, and money tips, click here.)

Robert teed up some major life/money situations and asked Garrett to point out the biggest mistakes people make. Here is an excerpt from their conversation.

Marriage
 TMF: What is the biggest mistake people make when they get married?

SG: They don't talk about money. It is not a romantic subject, but we must share our life goals with the person that we are marrying. If we haven't done it before marriage, we had better be doing it during marriage because [those goals] do evolve and change.

We say financial planning is a process. Well, when you are in a financial partnership with another individual, you need to step back and share what your individual goals are -- short-, medium-, and long-term -- as well as what your collective goals are as a couple and for your family. "Honey, where would you like to retire?" "We need to make sure we have room for our grandkids." That actually can be really romantic.

College costs
 TMF: How about the No. 1 mistake people make while they are saving or paying for college?

SG: A lot of parents make a pledge to their children that goes something like this: "Hey, you get into any school, and Mom and I will take care of paying for it."

Unfortunately, the majority of baby boomers -- this would be the audience that [has] kids in college right now -- don't have their own financial situation in good enough shape to be paying for kids' college, too. Yet they have made that promise to their child. There is nothing like breaking a promise to your child to break your heart. So don't stick it out there.

I encourage parents to strongly consider having Junior take out loans (and if you need to take out loans ... to cover the tuition, that's fine, too). But there is nothing at all wrong with ... junior college or just state university, because statistically the majority of us do not use our degree[s] in the work that we do later in life or even earlier in life. It doesn't make a hill of beans where we went to college.

[For the sake of] the rest of your financial household, you need to ... take care of yourself first. There is no such thing as financial aid in retirement.

Real estate
 TMF: What is the biggest mistake people make when buying a home?

SG: House buying is a very, very emotional thing. That is also a problem with it. We don't go into house buying logically and as an investment. We listen to our mortgage broker, real estate broker, and maybe even our own gut. We frequently will see that there is a huge difference between the definition of affordable and what you can qualify for when it comes to a mortgage.

Just remember the adage, "Everybody wants to part you from your money." [Mortgage brokers want] to get you into as much house as you can afford, according to their qualifications. As long as they have got a lender willing to give you the money, all they are doing is brokering the loan. So the biggest one they give you or get for you, regardless of whether it is in your best interest, the more money they make. Same thing with your realtor.

Work with a financial planner and find out, really, in all honesty, what can you afford with regard to your home and still have a life. Do you want to be house poor and completely poor in the rest of your life, or do you want to have some kind of balance? The mortgage broker and the real estate broker are doing everything within their power -- and we would expect them to -- to sell you as much house as you qualify for, which is very different than ... what you can afford.

Breaking up
 TMF: How about the No. 1 mistake people make when they are surviving a divorce?

SG: Women historically have wanted to keep the house and that [often] is not the right decision. There is a lot of emotional trauma and adjustments that we have to go through. Sometimes we need to step back ... take inventory.

Where are you at? What do you need to focus on? And if you have children, how are you going to ... provide for your children [and] for yourself as an individual, and start moving forward in life?

I don't believe there are financial-planning emergencies. If you need some guidance, get it. If you are not ready for it, then just be patient. If you start to feel confused, then surround yourself with ... people who can help provide that clarity of direction.

Burying your head in the sand will not improve things, but it is very normal to take your time [and] allow your emotions and your scars and bruises ... to heal a bit before you make any drastic decisions regarding selling or keeping the house.

More independent, objective money advice
For more of our interview with Sheryl Garrett and advice on estate planning, surviving the loss of a spouse, elder care, and getting the most from your earning potential, read the transcript on the Rule Your Retirement website. If you're not currently a subscriber, click here for free access for 30 days. In this month's issue, we show you the best way to buy bonds, how to set up a trust, what you can learn (and earn) from what corporate insiders are buying, and more.

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