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The clock is ticking toward the April 15 tax filing deadline. In the rush to get your return ready, it's easy to overlook some lucrative deductions. This year, there's more confusion than usual, thanks to the last-minute fiscal cliff deal that extended some tax breaks but not others.

The weak economy and high unemployment rate have made some credits and deductions relevant to people who may not have qualified for them in the past.

Here are some tips from tax pros to get all the breaks you deserve:

Know the true value of your charitable donations. Some people may be guilty of inflating their charitable contributions on their tax returns, but TurboTax Vice President and CPA Bob Meighan suspects far more undervalue what they give to charity. Some particularly easy to overlook contributions include mileage, out-of-pocket expenses and the value of used goods.

You can't deduct the value of your time, but if you itemize you can take a tax break for mileage incurred driving to and from your volunteer commitments. (If you don't itemize, you can't write off any charitable contributions.) The rate isn't exceptionally generous — just 14 cents per mile — and you'll need to keep a record of how many miles you drive, the day you drove them and the charitable purpose.

Out-of-pocket expenses incurred while volunteering are another potentially deductible expense.

"If you're a Boy or Girl Scout leader, mail birthday or get-well cards for a charitable organization or prepare food for your local soup kitchen, keep track of the cost of the adult uniforms, books, postage and even the ingredients you purchased for the food so that you might deduct the amount on your taxes," said enrolled agent Cynthia M. Jeanguenat of Virginia Beach, Va.

Liz Weston // Liz Weston (Liz Weston)

Liz Weston

Clothing, furniture, toys and other used goods donated to good causes could reap you a far more substantial deduction. The IRS allows you to deduct the fair market value of such goods, and those values tend to be significantly more than you could sell the items for in a yard sale.

TurboTax's free sister site, ItsDeductible, provides values for thousands of items based on the prices they fetch on eBay. Those nearly-new hardcover books you're practically giving away in your garage sale could have sold for $7 on the auction site. Since your tax break is equal to your tax bracket, that $7 would equal $1.75 off your taxes if you're in the 25% bracket.

Document each donation with an itemized list of items and their values. Take a snapshot with your camera or phone as further proof. And get a receipt from the charity.

You'll find more details in IRS Publication 526, Charitable Contributions.

Take credit for retirement savings. Low- and moderate-income taxpayers get an extra tax break if they save for retirement. Not only are their contributions to retirement accounts typically untaxed, but they also can get a credit that can reduce their tax bill by up to $1,000. (Credits are usually better deals than deductions, since they offset your tax bill dollar for dollar.)

Contribution to individual retirement accounts (IRAs), Roth IRAs and workplace retirement plans such as 401k's and 403b's all qualify. The credit, which equals up to half of the first $2,000 you contribute, starts to phase out as income rises. But single people with adjusted gross income up to $28,250 and marrieds with incomes up to $56,500 qualify for at least some credit. The income limit is $42,375 for heads of household.

You can learn more in the retirement tax credit section of the IRS site and by reading IRS Publication 4703.

Offset medical expenses. Your health costs have to be fairly hefty to qualify for this deduction. Only medical expenses in excess of 7.5% of your adjusted gross income qualify for the write-off in 2012. The minimum rises to 10% for tax year 2013 for taxpayers under 65.

But the weak economy makes it more likely that people have qualified for this deduction.

"People overlook this because they're not sure they qualify," Meighan said. "With the economy being so tight and unemployment so high, their incomes may have been significantly reduced over the years, so it's easier for many people [to take the deduction]."

Out-of-pocket costs for doctor visits, hospital stays and prescription drugs all count toward the total, as do weight-loss and smoking-cessation programs if your doctor prescribes them.

Your mileage to and from treatment can be a write-off, too, at 23 cents a mile. So can other transportation costs such as tolls and parking. You can find more information IRS Publication 502.

What doesn't qualify? Over-the-counter medications, including nicotine patches and gum, trips or programs to improve your general health and most cosmetic surgery.

Write off your move. Job-hunting expenses can be deductible, but they have to be substantial (more than 2% of your AGI), and you have to itemize. If you actually find a job and have to move, however, you are far more likely to qualify for a tax break.

The moving expense break "is an 'above the line' deduction. You don't have to itemize," Meighan said. "It's an adjustment to your income."

To qualify, your new workplace typically has to be at least 50 miles from your previous home, and you have to work full time for at least 39 weeks during the 12 months following your arrival at your new job location. The time test can be waived in case of death, disability, layoffs and other factors. Also, if you're a member of the armed forces and you were ordered to a permanent change of station, you don't have meet the distance or time requirements. For more information, check out IRS Publication 521, Moving Expenses.

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