The day before he shared a photo of the outside view of Stone Street Studios, the custom-built sound stages in Wellington that are housing the Avatar production.
The studios have been used for several blockbuster productions including King Kong, the Lord of the Rings, the Hobbit, and the original Avatar film.
The return of Cameron and his 32 crew members raised some eyebrows among Kiwis who grumbled about Hollywood stars getting special treatment though borders remain closed to non-New Zealanders.
But Landau told 1News that while they had special permission to return to New Zealand, it would help boost the region's economy.
"This one production alone is going to hire 400 New Zealanders to work on it," he said.
"We're going to spend, in the next five months alone, over $70 million here."
It comes as New Zealand lifted all restrictions apart from border controls after it was declared virus-free last week.
The Avatar crew were allowed back in on economic grounds, as a handful of productions start up again to revive the film business.
But border controls could tighten after two women who arrived in the country from the UK tested positive for the virus this week.
Landau said the opportunities were "immense."
"We are just the wedge in the door that hopefully unlocks a lot for the economy."
Cameron is directing Avatar 2 and 3 at the same time, as the first sequel is due to premiere in December 2021.
He revealed that Avatar 2 will be followed by Avatar 3 in December 2023, 4 in December 2025, and 5 in December 2027.
The second Avatar film stars Zoe Saldana, Kate Winslet, Sam Worthington, Vin Diesel, Michelle Yeoh and David Thewlis.
