TOLEDO (WTOL) - Parents want what’s best for their kids. Helping them become independent and successful can be expensive. It could mean adult children are still living at home, well after college graduation.

BGSU freshman Cassandra Clay is living at home while she gets her degree in early childhood education.

“I wanted to live off campus, but we decided it would be better if I live off campus here, since we live so close,” says Cassandra.

Mom Linda says she wants to help her daughter save any way she can, before those student loans start rolling in and couldn't justify the cost of room and board.

“What her bill is going to be when she leaves is going to be substantially less,” says Linda Clay.

Linda says even though Cassandra is staying home rent-free, it’s still important she learns responsibility.

Cassandra maintains her car expenses. Plus, she makes some money too.

“I babysit during the week and on the weekends,” says Cassandra,

The Clays are like many families who have young adult children living at home. Merrill Lynch did a study that shows parents spend $500 billion a year supporting their kids, ages 18 to 34.

Gilmore Jasion Mahler LTD CPA Charlie Heid gets it. He has 2 college age kids at home.

Heid says where the problem comes in is the second figure in the Merrill Lynch study.

Nationwide, parents are only putting $250 billion into retirement. That’s half what they’re spending to support their adult kids.

The study also says 80 percent of parents are taking a financial hit.

“So at the cost of their future, they’re covering costs for their kids,” said Heid.

Heid says it's important for parents to have a little tough love as your kids move to financial independence. Set limits.

“Talk to your kids up front and say, ‘I’m willing to cover four years.’ If one of your kids ends up on a five year plan, they’re on their own for that last year,” says Heid.

He says to have a plan for what to do once your child gets his or her degree. If you're past that point, it's time for another sit down.

" Kind of a contract with your kids at that stage, saying, the expectations are that they are not going to be paying for rent, but you should have a dollar amount in mind of what you’d like for room and board," says Heid.

Heid says parents might have to do some number-crunching to know how much they need to save to retire when they want to and then adjust how much they’re spending to support their adult kids.

He says it might actually save you money if you pay for a security deposit for your child’s first apartment.

“The way a parent has to look at it is ‘what’s it costing me over the long term to be in the home?’” Heid said.

Linda says she and her husband make sure to save for retirement and there will come a point when Cassandra is on her own.

“If you are putting money away and go out on your own and start on a solid foundation, then great. But if you’re not being smart with your money when you’re living at home, we’re going to charge you rent,” says Linda.

Heid says when your kids do leave the nest, it's important to make a clean, financial break. Make sure to stop paying expenses like car insurance and the cell phone bill.

You can find budgeting tools, and guidelines on drafting a contract with your kids here.