Updated

An American family expects they'll be able to stay in their home built inside a cave after accepting an offer of a private mortgage contract.

Curt Sleeper said Tuesday that a New Jersey-based business offered a 15-year loan with a low interest rate that should allow the family to keep their home in Festus, about 30 miles south of St. Louis.

"We're excited about it." To celebrate: "We're throwing a party at a friend's cave," he said.

Click here to see photos of the cave house.

Curt and Deborah Sleeper fell in love with the unique geography of an old mining cave in 2004 and figured out how to build a house inside of it. But they were having trouble making a large payment that was coming due on the property, prompting them to put their home up for auction on eBay.

They no longer plan to auction the home through the Web site, but Sleeper says the house will remain there until paperwork is completed on the loan.

Jon Demarest, owner of Logical Source Inc., confirmed that his the Fairfield, N.J.-based archiving and medical record company offered the Sleepers a mortgage.

"I was intrigued by it," Demarest said. "Someone who has put that much into it shouldn't lose it."

The Sleepers built their cave home with the help of friends. A gray timber frame exterior was constructed in the 37-foot-tall opening of the cave. Thirty-seven sliding glass doors also are used as windows throughout the three-story, three-bedroom home, allowing natural light throughout the finished sections of the home.

The walls and ceiling are natural cave stone, but it has amenities including a large soaking tub in one bathroom and a fully equipped kitchen.

Sleeper said his family's struggle to keep their home has resonated with many, including some who have been unable to pay their own mortgages.

"I've got 8,000 e-mails in my inbox. Everyone wants to wish me luck, but also tell me their heartache," he said.

"It's certainly been almost life changing -- except I'm keeping my cave, so not that life changing," he said. "I'd love to hear the end of the story read, 'and they lived happily ever after."'