How to Handle Living with the 'Rents

More young adults are moving back in with their parents.

More young adults are moving back in with their parents

Plan, too, for personal goals and roles like duration of stay and the extent to which the child will contribute, such as helping with chores or the mortgage. "The more that both parent and adult child can do these things, have these conversations ahead of time and have some basic agreements and ground rules, in all likelihood, the better it's going to go," Coleman says.

Meanwhile, savor the perks. "Family is your lifeline ... It's the safe place, plus you have all the benefits of a washing machine you don't have to pour quarters into," Newman says.

But be careful to avoid becoming too comfortable or, worse, regressing. Newman suggests young adults assert themselves if they feel their parents are interfering by saying something like: "When you talk to me about my hair, my clothes, my dating habits, my job hunt, it makes me feel as if I'm 10 years old again." Parents should, ideally, get the hint, she says. But it's likely to take some time to readjust.

"There are going to be bumps along the way as you get used to living with each other again because this adult child is not the same person who left four years ago or six years ago, and you want to view it as an opportunity to strengthen your bond," Newman says. "You're building a lifelong relationship, and it's a real opportunity to know each other as people rather than as parents and child."

[Read: How and Why to Become a Morning Person.]