WASHINGTON (AP) — President Barack Obama says millions of Americans can save money by refinancing their homes and taking advantage of record low rates on fixed mortgages. Speaking at the White House, Obama on Thursday emphasized that that average rates on 30-year fixed-rate mortgages have dropped to 4.78 percent. That is the lowest rate on record. Said the president: “People can really take advantage of this.” Obama touted an increase in refinancing nationwide as a sign that federal programs to help homeowners are working. But he warned people to watch out for scam artists. He said if people offering to help people stay in their homes ask for money upfront then “it’s probably a scam.”