A year on from purchasing the 1903 building from the Awabakal Local Aboriginal Land Council, Dr Schwartz is on the verge of lodging a development application with City of Newcastle for the building works.

"I'm just waiting on the heritage report, that will be the last consultant's report we need before the DA is lodged," he said.

Australia Post decommissioned the building in the late 1990s, partly because of the large quantities of asbestos that were present.

Awabakal with the assistance of the NSW Aboriginal Land Council and the NSW Office of Environment, began work on a $300,000 project to remove the asbestos prior to selling it to Dr Schwartz.

With almost all of the asbestos now removed, Dr Schwartz, who paid $3.5 million for the building, said he was keen to progress the development application and start construction.

"There haven't been any unexpected issues and our plans are unchanged," he said.

"There's a small bit of asbestos still in the roof near the plant room but that can't be touched until the DA is approved," Dr Schwartz said.

"If things pan out as I hope we will start work on the Aboriginal cultural area in the basement."

It is hoped the area could be complete by the end of the financial year.

The building's first floor will be used as a function centre, while the ground floor will feature wedding retail outlets including dress shops, florists and photographers.

Dr Schwartz was among 11 hospitality and educational organisations that lodged expressions of interest to acquire the building in late 2017.

He previously said he did not intend to turn an immediate profit from the post office project. Rather, Dr Schwartz said he bid for the site because it complimented his Newcastle property portfolio and because of his confidence in the city.

"It's a highly significant building that is important for the history of Newcastle. I think it epitomises the fact that Newcastle is being reinvigorated, just like the rest of Honeysuckle and slowly Hunter Street," he said.

Dr Schwartz, who operates two amphibious aircraft at Cessnock Airport, is also a part owner of Sydney Sea Planes.

He said he hoped the new venture would help create enhanced transport links between Sydney, Newcastle and the Hunter Valley.

"The idea is not only to expand the sea planes between Sydney and the Hunter but to open up a scenic sea plane service from the harbour and offer scenic flights to the Hunter Valley," he said.

"I'm also planning bring a coach service to connect Newcastle Airport with Newcastle and the Hunter."