When you want to learn more about smart investments and the best ways to invest, you won't have any trouble finding people willing to help you. What you may not realize, though, is that the financial institutions that offer their help usually have their own agenda -- and it might be completely contrary to your own financial needs and goals.

Bogle on predatory investing
John Bogle, who founded the Vanguard Group, knows all too well the impact of Wall Street's greed. In a recent Moneywatch interview, Bogle described Wall Street as an "extractive industry," in which "customers don't come anywhere near getting what they pay for."

Certainly, the numbers speak for themselves. Asset management companies like Franklin Resources (NYSE: BEN) and AllianceBernstein (NYSE: AB) are highly profitable, with healthy margins. And though those profits can move around a lot depending on the market, you can always rest assured of one thing: when the market drops, those companies won't be giving you back any of the money you paid for fees.

Moreover, Wall Street companies have too many constituencies to serve. In addition to customers, employees and shareholders all clamor for a piece of the pie. For every penny Goldman Sachs (NYSE: GS) and Morgan Stanley (NYSE: MS) pay out in bonuses to employees, that penny had to come from somewhere. Guess where? From you, the customer.

What you can do
But, you aren't powerless. Thanks to numerous resources available to investors, you can do a lot to reduce the amount of overhead you lose to Wall Street firms. Here are a few choices you have:

1. Be smart about your broker.
If you're not using a discount broker, take a hard look at whether the financial professionals you have working for you are really earning their keep. Sure, discount brokers may not call you on the phone or invite you to play golf with them, but when it comes time to pay the bill, you'll notice a big improvement.

Of course, discount brokers themselves have their own financial incentives. Schwab (NYSE: SCHW) was the first player in the discount brokerage industry, and though it has recently cut its commissions, it recognizes that trading volume is a key measure of its profitability. Competitors TD Ameritrade (Nasdaq: AMTD) and E*Trade Financial (Nasdaq: ETFC) similarly feel the pressure to perform. That's why you'll see all of them emphasizing trading tools that promote frequent moves in and out of stocks and the market overall.

But just because those features are available doesn't mean you have to become a day trader. The same tools can help you make long-term investments and track your progress on a regular basis. So, find a broker that fits with your style and will help you reduce costs as far as you can.

2. Keep investments simple.
Whether you buy individual stocks or mutual funds, there's value in keeping your portfolio simple. If you invest in stocks directly, then a well-tailored portfolio will help keep your trading costs down. If you prefer funds, then going with low-cost mutual fund providers will save you money year in and year out while still giving you the same or better chances to achieve winning performance.

For many investors, a core portfolio of ETFs and index mutual funds is a good spot for the bulk of your money. With the rest, you can afford to invest in promising companies or sectors of the market that have above-average potential for growth. That approach isn't going to make your broker or fund company rich, but it might just make you wealthy.

3. Keep your eyes open.
One thing Wall Street companies have going for them is a long reputation for historical excellence. Too many companies, however, coast on their reputations even when their business has fundamentally changed.

For instance, Bogle has been vocal in criticizing Vanguard for its push into ETFs. Bogle sees ETFs as tools that encourage short-term trading rather than long-term investing, and as such, believes that investors are better served with mutual funds. Yet, proponents point to the relatively low costs of Vanguard's ETFs as a sign that the company is continuing in its tradition of providing value to customers.

It's your money
Given how hard you work for your money, it's a shame you have to defend it from the people offering to help you. But by being diligent and recognizing potential conflicts of interest among professionals who seek to advise you, you'll be better prepared to confront them when they offer questionable advice -- and you may eventually get to the point where you no longer need them at all.

If you're paying for a full-service broker, you can't afford to wait another minute. Check out the Fool's Broker Center, and find a discount broker that will save you tons of money.

Tune in every Monday and Wednesday for Dan's columns on retirement, investing, and personal finance.

Fool contributor Dan Caplinger thinks the best offense is a good defense. He doesn't own shares of the companies mentioned in this article. Charles Schwab is a Motley Fool Stock Advisor selection. Try any of our Foolish newsletters today, free for 30 days. The Fool's disclosure policy offers protection at the best price -- free.