SAN DIEGO -- Mortgage rates are the lowest they've been since Freddie Mac began tracking them in 1971, experts said, and for homeowners thinking about refinancing their home, this may be the time.

A 30-year fixed-rate loan, on average, is at 4.54 percent, while a 15-year fixed-rate is at an even 4 percent.

"If you can quality, if your home has enough equity, if the value hasn't taken away the opportunity to refinance, this is a perfect time," said mortgage broker Robert Feher.

Peggy Landon of Sabre Springs started thinking about refinancing two months ago, and she was surprised by how low the rates had gotten.

"I actually never thought they would stay below 5 [percent] for as long as they have," she said.

She wound up getting a 30-year fixed-rate loan for 4.375 percent, which will save her about $200 a month.

"When it got to the rate I was comfortable with, I took it," she said. "I know they're down again today, but I'm already locked in and I'm happy with what I got."

The savings can be significant. For example, if a homeowner has a $300,000, 30-year fixed-rate mortgage, at 6 percent, the homeowner is paying $18,000 a year in interest. If the home is refinanced at 4.54 percent, the homeowner would be paying $13,500 a year -- a savings of $4,500.

Experts said getting that new loan can be difficult as many lenders are cautious these days.

"If you meet their criteria, no problem at all," said Feher.

However, if a homeowner's situation is somewhat out of the ordinary, it's tougher.

"You could find yourself with a lot of heartache and a lot of extra documentation to prove you are a credit-worth borrower," said Feher.

Feher said homeowners can get a very good rate paying either no points or at the maximum one point to get a loan.