Ngangan, who is also the Finance Secretary, told The National newspaper this week that the process of stock-taking and accounting for all the assets owned by the authority was under way.
The disposal of the assets through the public tender process will start after that.
"We are finalising the list of all assets purchased by the authority including the vehicles," Ngangan said.
"We will this week send out letters and public notices for all assets to be returned to a common location. Once all assets purchased by the authority are accounted for, we will start the public disposal process through public tender."
He said the tender board would work with the government to decide which assets should be allocated to public institutions and which ones to be sold.
"All these processes will be undertaken and managed publicly and transparently for all to see," he said.
The National reports that APEC Minister Justin Tkatchenko earlier said the APEC Authority would cease to exist at the end of next month. For that reason, all assets owned by the authority would have to be disposed of through public tender before the end of December.
Tkatchenko said proceeds from the sale of those assets would assist the government recover some of the money spent to host the APEC Leader's Summit this month.
Some of the buses donated by the Chinese government will be given to the National Capital District Commission to be used for free public transport in Port Moresby, The National reported.