Real estate agent David Dunworth told the Queensland Floods Commission of Inquiry he bought a luxury unit at the Tennyson Reach complex, which adjoins the State Tennis Centre at Tennyson on Brisbane's south-side, without doing a flood search on the property.
The unit, along with another one in the complex he was leasing, was inundated during the Brisbane floods in January this year.
After the flood, which caused major damage to his unit and destroyed furniture, art and other belongings, Mr Dunworth said he discovered his unit was more than two metres below the 1974 flood level.
He also discovered regulations that required the property to be set back 20 metres had been relaxed to allow his unit complex to be built just six metres from the river.
"I think if I had known all these things we would have considered making a different decision," he said.
He said sellers should be required to provide the information up front.
Mr Dunworth said he believed that since a major property developer, Mirvac, was behind the project and it had the backing of the state government and planning approval from the Brisbane City Council, all necessary precautions would have been taken.
"I just assumed that the most stringent conditions were being imposed," he told the inquiry.
The values at Tennyson Reach have dropped by 30% to 50%.