That’s exactly what happened St Georges Basin couple Andrew and Hayley Dolphin.

As part of McDonald Jones Homes 30th birthday celebrations the company is giving away $300,000 a month, with the Dolphins the third family to have won a birthday celebration prize.

When the couple turned up at the company's Twin Waters operation at South Nowra on Monday, they thought they were going to check on a few things about their new home to be built at Tomerong.

They never expected such a ”life changing” announcement.

“This is mind blowing,” Andrew said.

“Life changing,” Hayley said.

The couple are just at the planning stage of their new “dream home” at Tomerong.

“We still have a fair way to go,” Andrew said “but this will make the planning a lot more fun,” Hayley said.

“We can’t even express what this means,” Hayley said.

“We never thought anything like this would happen. It’s just amazing.”

Andrew thanked the company for the “incredible” prize.

“This will virtually allow us to own our home,” he said.

“It will certainly make things a lot easier.”

McDonald Jones Homes head of marketing Nathan Thurston said the company has so far given away prizes to three families, totalling just almost $900,000.

“This is the third prize we have given away as part of our 30th birthday promotion,” he said

“It is the first time we have awarded a prize on the South Coast and we have nine more prizes to giveaway over the next nine months.”