(MONEY Magazine) – Q. With our second child on the way, my wife and I know we need a will, but we can't spend a ton of money. Is it okay to create our own online?

A. You're right, you do need a will, even if you don't have much money, because it's the only way to appoint a guardian for your children. Otherwise, if you and your spouse both die unexpectedly, state law will decide who raises your kids, not you. If you have less than $2 million in assets and your bequests are straightforward--you want to leave most everything to your spouse and kids--an online do-it-yourself site (or software) is fine. Some good choices: BuildaWill.com ($20) is suitable for creating a very basic document that names a guardian and a few heirs; Quicken's WillMaker Plus ($50 in stores; $40 online at nolo.com) allows for more complex situations. However, if you own a business, expect anyone to challenge the will or want to place conditions on an inheritance (say, Junior can't touch the money until he turns 30), you should consult a lawyer. Expect to pay a minimum of $500 to $1,000, with additional charges if you need a trust as well.