Ryan Ferrell, a senior manager at a Chicago-based ad agency, isn't your average 25-year-old. He's saved enough to put a sizeable down payment on a condo in the city's trendy South Loop and even qualified for a conventional loan. How has he pulled this off?

Here's a hint: It's not what he's done. It's what he hasn't done that has made the difference.

Ferrell isn't alone in using this technique. We talked to professional penny-pinchers, who agree that this one thing can cost you thousands of dollars. It's something you do thinking you'll save money. But in reality, it wastes money. Stop doing it and you'll have plenty of cash to finance the things you really want -- vacations, a nice home, a cushy retirement.

Here it is: Get rid of all those habits you think are saving you money. That's right. In your quest to save money, you've actually fallen into habits that waste money.

With the help of Ferrell and others, we came up with five so-called money-saving myths that really drain your funds -- and ways to change your habits to avoid them.

1. Free shipping: Most free shipping comes with a cost: a minimum purchase. One example: A site offers free shipping with a $50 purchase or $4.95 for standard ground shipping without that minimum. If you need only $20 worth of product, you're actually spending $25 ($50 - $20 - $4.95 rounded up to $5) to get that free shipping.

The fix: Do the free-shipping math first. Or stock up and purchase several things at once, as budget-conscious blogger Shawanda Greene does. She fills her online Amazon.com cart with essentials as she needs them, then clicks 'buy' once she hits the minimum-purchase amount. As a result, Greene never pays for shipping, saving hundreds of dollars a year.

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2. Free trials: It's tempting to sign up for monthlong free trials to Amazon.com Prime, online magazines and job-hunting sites. But forget to terminate your subscription before the trial ends and you start paying that monthly or yearly fee for the service.

The fix: Greene, who blogs at Youhavemorethanyouthink.com, sets several alerts on her smartphone to cancel the free trial a few days before the fee would kick in. Greene just canceled two subscriptions that would have cost her, all told, $36 a month. That's $432 a year in savings.

3. Paid-for cars: Ferrell's car -- nothing fancy -- is paid for. But that doesn't mean it's cost-free. In fact, owning the vehicle costs him about $2,700 a year, counting gas, insurance, maintenance and Chicago-required city sticker.

The fix:

Ferrell has done the math and figures the car costs him $324 a month, a figure that would include a heated parking garage near his new condo. The iGo or Zip Car car-sharing program, he figures, will cost him $58 to $75 a month, so not owning a car will save him at least $249 a month.

4. Big savings from daily-deal apps: These apps, which store your credit card number, make spending money as easy as pushing a button. That's the bad news. The worse news is that 20% of the average American family's disposable income is spent on such impulse buys, said Phillip Fremont-Smith, co-founder and CEO of ImpulseSave, a Cambridge, Mass.-based company whose app helps consumers save money. (The calculation comes from U.S. Department of Commerce, Bureau of Economic Analysis and other data, Fremont-Smith said.)

The fix: Find an app that helps you save, not spend. ImpulseSave users, for example, can transfer money to their savings account when they impulsively decide to, say, not spend $50 on a new sweater and save that money instead. Users can program the app to send friendly (and frequent) reminders of savings goals, such as for a vacation or to pay off student loans.

'We want to be a little bit in your face,' Fremont-Smith said of the app's strategy. The savings depend on how often the user actually saves rather than spends; not buying a $20 Groupon a week would result in savings of $1,040 a year.

5. Cheap chic: At the turn of every season, retailers beckon us to 'invest' in the 'hot trend,' be it color-blocked dresses or platform pumps. It's tempting to indulge those trends at one of the palaces of cheap chic -- H&M, to name one -- that offer runway looks at a fraction of the cost. However, those clothes usually don't last very long and three months later they're hopelessly out of date.

The fix: Ferrell likes stylish clothes that fit well. His mantra: 'I buy once.' In other words, he shops for well-made classics, including dress shirts, but finds them on sale or at a deep-discounter (Marshall's, for example). He then pays a tailor $15 to nip in the neck and seams. The result? He pays about $30 per shirt, even less than nice dress shirts are when they go on sale at department stores. He stresses, though, that price is hardly the be–all, end-all: 'You still have to go for something quality,' including solid construction and a nice, long-lasting fabric, he said.

The Investing Answer: Use that powerful money-saving tool that is your brain. Admittedly, with an overload of media these days, it's not easy: 'You have to be in a cave in Afghanistan not to be marketed to,' Fremont-Smith said. It's not easy, but it's possible. Ferrell, for one, thinks of purchases in terms of how much that money can earn him in retirement. Take, for instance, the iPad he wanted.

'At a $30-an-hour salary, a $500 iPad would take two working days to pay for,' he said. Not bad, but consider that in 30 years, with an 8% return, that same $500 would turn into $5,000.

'Would you rather retire three months early, or have that iPad?' he asks.