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Tax shelters have been described by the unsophisticated as gimmicks or "loopholes." The fact is, Congress created these loopholes, after careful deliberation (we hope), to serve some major economic or social goal.

A tax shelter is any investment designed to reduce or avoid income taxes. This is not bad. Former Internal Revenue Service Commissioner Donald Alexander once said, "As a citizen, you have an obligation to the country's tax system, but you also have an obligation to yourself to know your rights under the law and possible tax deductions -- and to claim every one of them."

Traditional tax shelters have included investments in real estate, oil and gas, equipment leasing, and cattle feeding and breeding programs.

Real estate is a great shelter

Real estate is the most popular shelter. Indeed, it's such a good tax shelter that, as Rep. Pete Stark, D-Calif., put it memorably: "It'd take a genius to invest in real estate and pay taxes." Real estate provides leverage, an inflation hedge, cash flow and equity buildup.

As your property appreciates in value (eventually, we hope), you are allowed a paper deduction for depreciation. If structured correctly, you buy the property with your down payment. Hopefully, your rents cover your mortgage interest, taxes and operating expenses.

But it's possible to come out ahead even if the property loses money. Remember, in the 28% tax bracket, a $5,000 paper deduction for depreciation creates a real cash tax savings of $1,400. This tax-generated cash can be used for any operating expense deficit.

Moreover, as you pay down the mortgage, you're building equity. It's a win-win situation. Once your mortgage is paid off, you have an annuity in perpetuity (rents), while owning something that historically has appreciated in value. The downside is that you must buy property that will appreciate in value, and, if you want to deduct your losses, you must be actively involved in its management. You can get killed if you super-leverage and the price of the real estate crashes. Remember the bubble and be careful!

On the other hand, if you have cash or credit, with historically low interest rates and depressed prices, now may be a great time to invest in real estate.

Oil and gas: No guarantees

Jeff Schnepper

Jeff Schnepper

Oil and gas investments are sold through limited partnerships marketed by major brokerage houses.

With oil and gas, you're allowed to deduct as a current expense your investments in capital expenditures known as intangible drilling and developing costs. Nearly all the costs of drilling and completing a well are deductible in the year incurred. Normally, you would not be allowed to deduct these expenditures until the year that either the product was actually extracted from the wells or the drilling was abandoned.

Moreover, with these investments, you can use either cost depletion or percentage depletion.

The downside is there are never any guarantees you will hit oil or gas. These deductions lose their shine when there is no income to offset them. You can minimize your risk by investing in development or combination programs rather than in wildcatting, as exploratory drilling is known.

Keep in mind, however, that as you reduce your risk, you also reduce your potential investment profit. Wildcatting produces the greatest returns, but it also has the lowest probability of success.

Equipment leasing: Structure correctly

Equipment leasing investments are also marketed through limited partnerships. They are used for financing computers, airplanes, railroad rolling stock, ships, etc. In many cases, a partnership provides the money to finance the purchase (hugely leveraged), which is leased to the company that uses it. The lease payments are used to amortize the debt.

With equipment leasing, your shelter comes from accelerated deductions and the use of the power of leverage in structuring the program.

In the early years, you can actually deduct more than the cash you put into the deal. However, in the later years, you may have what is known as "phantom income."

This occurs when your taxable income is greater than your actual cash inflow. By taking the deductions in the earlier years, you have fewer deductions available in the later years. While the amount of interest you pay on your investment loan is reduced, the payment itself is not. You are now paying principal, which is not deductible.

Nevertheless, structured correctly, an equipment leasing shelter gives you the opportunity to get an interest-free loan from the IRS by paying less in taxes today and making it up tomorrow.

Make sure economic reality and a profit objective drive your investments. Don't simply look for the availability of tax deductions. If you are just looking for a deduction, send me a check. I will be happy to send you a receipt for a tax consultation that would clearly be allowed. Even in the top 35% tax bracket, you would still be out of pocket 65% of what you paid me. But I can live with that.

Cattle shelters not for novices

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Cattle feeding and breeding shelters also offer tax savings by accelerating the deductions and the potential exchange of ordinary deductions for capital gains. However, the economics of these programs can be seriously affected by the cyclical market price of cattle. These deals are not for the unsophisticated.

Certain shelters should be avoided completely. These include art reproduction shelters and noncash gift shelters. Both of these are frauds that will almost guarantee you an unhappy audit by the Internal Revenue Service. Single-premium life insurance and tax straddles have legislatively lost their tax shelter elements and no longer provide the tax savings opportunities of the past. While they might make sense on an economic basis, using them as a tax shelter won't work.

Jeff Schnepper is the author of the best-selling book "How to Pay Zero Taxes," which is in its 30th edition. He is a former professor of taxation, accounting and finance. Schnepper now has a full-time tax planning and legal practice in Cherry Hill, N.J. Click here to find Schnepper's most recent articles.