h, if life were really this simple. Common sense suggests that as a person of sound mind and body, you could make plans for your estate after your death with a few simple words on a piece of paper.

Better yet, with all the will-making software available, you could pull up a sample document on your computer screen and fill in the blanks. A notary public would sign and affix his seal, and a family member or close friend would sign it as a witness.

The document might say something like this:

Last will and testament: "I leave everything to my dear husband John."

Durable power of attorney: "If a doctor declares me mentally incompetent, my daughter, Christine, is authorized to make all financial and legal decisions for me."

Living will: "I do not want to be connected to life support systems for more than 24 hours if there is almost no chance I will recover."

Health-care proxy: "If I am declared mentally incompetent by a doctor, my brother, Sam, is authorized to make all medical decisions in my place."

Sounds easy, right?

But just like everything else connected with the law, estate planning is more complicated than it sounds. Granted, there's a lot less involved if you have a modest estate valued at less than $625,000, which is the current amount you can bequeath to someone free of estate taxes.

The rest of us, however, need to do a bit more investigating. And if you own a house that's built up equity over the years, chances are you're over the $625,000 threshold. You have to draft and sign estate-planning documents in just the right way so that they're considered legal and understandable. And you have to be especially careful about who you choose to sign as witnesses on those documents.

For years, stationery stores have stocked pre-printed forms that allow you to fill in the blanks, sign and date them and have them notarized. The advent of the computer has heralded a new era in do-it-yourself estate planning. There are some excellent software packages that allow you to draft the documents with language that more closely parallels your desires.

You are using a computer right now, so it seems reasonable to think that you could successfully navigate your way through a software program to create airtight documents that would stand up in court. And then, of course, there are estate-planning attorneys you hire to draft the documents based on your desires.

You can probably guess which of the three is the most expensive. You can also probably guess which one best ensures that your true wishes are carried out. (Here's a hint: The answer is the same for both.)

Your will is the most individualized of all estate-planning documents. The advantage to using a pre-printed form is cost (a few dollars). The problem is that it probably won't address your individual situation and could easily be challenged in court, costing you or your family tens of thousands of dollars. In the end, your money may be given away to people you hadn't intended. Or the wording might be incorrect and would not be valid in your particular state. That, too, would cost you dearly.

Software products cost more than pre-printed forms but allow for much more individual expression while costing less than attorneys. The better products offer excellent explanations of the various documents, variations in language to conform to the laws in your state and step-by-step instructions for doing it yourself.

Then, of course, there are lawyers. The advantage of using a lawyer is that he or she hopefully will know enough to get the job done right, to protect your will from challenges and to make sure that it complies with state laws in all respects. The disadvantage: cost. Legal fees usually average $75 to $200 an hour or more, depending on the complexity of the case and the demand for the attorney's services.

The best strategy is to do as much work on your own as you can and then see a lawyer. First, forget the pre-printed forms altogether. All they're likely to do is give you a false sense of security, when they're really inadequate.

Second, do your homework. The software programs are a good start because they provide educational explanations. The advantage of software programs over estate-planning books is that you can actually generate wills, trusts and other documents specific to your needs. Books are usually too general to use as a basis for creating documents.

Third, once you've done some initial work, consult an attorney. The good news is that if you used a software program, the time you spent at the computer won't be for naught. You probably saved yourself several hours' worth of legal fees by doing much of the preparation work.

When you see your attorney, you should bring a written list of the following:

Why always use an attorney? The answer is that even the best software program can't guarantee that the wording is exactly what you want and that it conforms to state law to make it airtight. (Of course, your attorney can't make that guarantee either but the odds are much, much higher). Laws are changing at lightning speed - witness the estate law changes passed in 1997. And many a beneficiary has inadvertently disqualified himself by signing as a witness to a will.

Your attorney may also be able to show you ways to save on estate and inheritance taxes as well as administrative fees (which usually run about 5 percent of the probate estate). If you're divorced and remarried, have children or want to disinherit any of your close relatives, not using an attorney could be a disaster.

If you're a die-hard do-it-yourselfer, you may want to consider paying a lawyer for one hour's time to simply review your work. Don't let your pride get in the way of smart estate planning.