BOSTON -- Selling a house can be stressful. And when the sale actually happens, another stressor: paying the real estate agent 5 or 6 percent in commissions.

Now there's a way for sellers to be their own brokers. And it's a lot more sophisticated than planting a "For Sale By Owner" sign on your front lawn.

Paul Costas isn't a real estate agent. But he was able to act as one.

"If I went with a regular broker, it would have cost me 5 percent, so I saved 2.5 percent," said Costas.

He saved thousands of dollars in commissions by listing his house himself on the Multiple Listing Service, usually reserved for brokers.

I saved $12,000 because of the 2.5 percent that I didn't have to pay the other broker," he said.

Traditionally, when you sell property, you give it to a licensed broker who lists it on MLS, sees it through the process, and gets half the commission. But now, there is a way to do it yourself.

"We give the consumer access to the MLS system that they're not allowed to get on their own," said Tom Carter, Founder of UCanlist.com.

For a flat fee of $300, you use his real estate license to get access and list your house on MLS. And because anyone can view homes for sale on MLS, a buyer can contact the seller directly. That means the seller also saves the commission he'd have to pay a buyer's broker.

"You can sell your house, and I've proven it many times," said Carter.

Independent seller listings are a relatively new idea. According to MLS statistics for 2009 in Massachusetts, of more than $36,000 single family homes sold, only 677 were listed by their owners.

Listing your home yourself on MLS is perfectly legal, but not everyone agrees it's a good idea.

"There's a lot more to selling a home than just putting it on the multiple listing service and waiting for buyers to come," said Jeffrey Chubb, a Realtor at Remax.

Chubb warns there are pitfalls to acting as your own agent. When sellers work alone, they're responsible for arranging showings, and forced to let strangers walk through their homes with virtually no pre-qualification. And they have to become professional negotiators.

"It's a lot harder for a seller to sit back and take the emotional ties out of selling a property," said Chubb.

Tom Carter agrees that selling a house can be daunting. So Ucanlist.com offers additional services, like staging and showings, at an additional cost.

It worked for Paul Costas.

"I would definitely recommend it to a person who wants to save money," said Costas.

The National Association of Realtors says there are definitely trade-offs with this approach because consumers are basically going into a real estate transaction with no one looking after their interest. At the very least, experts say, people seeking this option should consult with an attorney.