NEW YORK (CNN/Money) - Whoever said pending parenthood is a time of simple joy?

For expectant parents, there's nothing more stressful than trying to figure out just how to make room for baby as you make the transition from freewheeling couple to homebound Mom and Dad.

With the housing market on a tear, couples are opting to trade in the urban apartments for suburban life. And a baby on the way is proving to be a big motivator for couples to take the plunge into the real estate market, said Linda Murray, executive editor of BabyCenter.com and co-author of The BabyCenter Essential Guide to Pregnancy and Birth.

Murray said that expectant couples are twice as likely to buy a home than couples without children. If you're in that group, here are some things to keep in mind to help you make the best choice in homes without breaking the bank.

Young couples tend to make the mistake of buying overpriced homes that are more similar in style to those of their well-established parents, rather than looking for a more affordable model.

"Chief among the culprits of an unbalanced budget is a house payment that is far too much to handle," said Bryan Clintsman, a certified financial planner at Clintsman Financial Planning. "I am the one that has to sit down with these couples later to pick up the pieces of being house-rich and cash-poor."

Financial advisors say that homebuyers should try to keep mortgage payments below 28 percent of gross income. Your debt, which may include items such as student loans, car loans and credit cards shouldn't exceed 36 percent of gross income.

And new parents may have even less wiggle room that others. Remember, babies are expensive. A good rule of thumb is to factor in about $6,000 to $12,000 a year as the cost of a new baby, said Elaine Scoggins, president of Scoggins Financial.

In addition, new parents should be conservative with their income estimates. It's not uncommon for a mother or father to quit work or scale back their hours after a baby is born, even if that wasn't the original plan. Try to calculate a mortgage that would be manageable on one income if circumstances change.

That 5/1 ARM (which means its initial interest rate adjusts after five years and can change once a year after that) certainly sounds cheaper when you compare the costs of the interest rate on your mortgage to a 30-year fixed mortgage. The average interest rate for a 5/1 ARM is currently about 4.91 percent while a 30-year can run about 5.5 percent, according to Bankrate.com.

But beware the trap: a 5/1 ARM means that at the end of the 5-year period, your monthly payment will reflect whatever the current rate is and economists expect rates to continue to rise. New parents have enough expenses without worrying about a sudden spike in mortgage payments when Junior turns 5.

Avoid interest-only loans if you're considering this option to afford a home that would otherwise be outside your budget. If circumstances change, such as the loss of one income, you may not be able to afford the payments when the interest-only period ends and the mortgage payment spikes up significantly.

It's tempting to buy a house with granite counter-tops, marble tiles and a cute little rock pond in the backyard. But is it really necessary?

Instead new parents' primary focus should be the right amount of space and the right neighborhood to start a family -- better to pay up for a good school system that a sub-zero fridge.

In the home, try to avoid physical dangers like steep stairs, porches and decks with large drop offs or passageways with only a railing on either side. And invest in some serious baby-proofing if the home has some of these dangers.

Sure, it's tempting to move your new family into a starter home -- one that is usually smaller, may need a little more renovation and is generally less expensive than a large single-family home. For those on a tight budget, it could be ideal. But if your family suddenly expands further, starter homes may prove to be too small, said Clintsman.

Consider how many children you want in the future and how soon after the first child when deciding on the size of a home. If you consider that, on average, it costs about 10 percent of the home value to pay closing costs of buying and selling a house – not to mention the cost of hiring moving companies and buying furniture for a larger space – frequent moving around can take its toll on your wallet.

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