Should You Stay Home or Work Part-Time?

Living on one salary isn't all tag sales and garden salads -- you have to look at the big picture. Here are some financial steps you should take before quitting your job:

Run the numbers. Don't just add up your rent or mortgage, utilities, and phone and then guess the rest. Instead, look at everything you spent over the last three or four months. List fixed expenses that don't change from month to month, such as loan or car payments and mortgage or rent. Then take averages of expenses that vary, like utilities, phone, gas, groceries, gifts and entertainment, car maintenance, etc. And don't forget the last bit of unfixed expenses: cash. The amount of cash you mindlessly spend, says Monica Samuels, co-author of Comeback Moms: How to Leave Work, Raise Children, and Jump-Start Your Career Even If You Haven't Had a Job in Years, is often drastically underestimated by couples. The point is not so much to find ways to trim those extra expenses (that comes later), but to get a brutally realistic picture of what's going out relative to what's coming in.

Practice before you quit. If you're sure enough without detailed budgeting, or if you have run the numbers and can see in black and white that doing it is feasible, just do it! "Not only will you be testing your plan, you'll also be saving your salary to create a savings cushion," says Samuels. That said, it's actually the rare mom-to-be who is absolutely sure she'll either quit or return to work. So don't sweat it if you don't have the time to practice the one-salary lifestyle. If you're getting paid while you're on maternity leave, take your salary and put it in the bank instead of spending it. (And if you're not getting paid, you'll have a good sense of how you would manage.)

Don't forget the costs of working. There is, of course, the cost of childcare. Then there are commuting expenses, whether that means more gas tank fill-ups or train/bus/subway tickets. And although these are hard to quantify, factor in such costs as lunches out (not every working mom can brown-bag it every day!), dry cleaning, and buying new duds suitable for the office.

Think (way) outside the box. Were you thinking of upgrading to bigger digs to accommodate your growing family? Maybe now's not the time. Kristine and Jose Acevedo live in the same two-bedroom home Jose bought before they married. "Sure, I'd love to have more room to entertain our families, but we already know we can afford this house on his salary alone, so we're staying put," Kristine says.

Economize without (much) pain. If your family is like most Americans, food is probably your biggest unfixed expense. According to Jonni McCoy, founder of Miserly Moms (miserlymoms.com), it's also the one that you can most easily, and creatively, cut down. The way to do it is, in a word, planning. "I spend probably seven hours a week making menu plans, finding and using coupons, shopping, and cooking," McCoy says. Other budget trimmers aren't too draconian. Limit your cable; you can always get a cheap Netflix subscription to catch up on your favorite HBO drama. Find low-cost or free entertainment in your area, such as free days at museums or zoos, free children's shows, concerts in parks, and so on.

If you are making the leap to being a stay-at-home mom, there's one piece of advice to remember: Your kids are only small for an agonizingly brief period of time. And remember, says Sally Herigstad, who stayed home until her kids were teens, "a large segment of the population makes this decision -- and makes it work."