Immigration visa services general manager Nicola Hogg said investors needed to show they met the criteria, including health, character and English language requirements.
"The residential property must be in the form of new developments ...[and] must have been approved and gained any required consents by any relevant regulatory authorities," Ms Hogg said.
The principal investor must be no older than 65 and have at least three years' business experience.
"The investment made must not be for the personal use of the applicant and this includes investing in assets such as a personal residence," Ms Hogg said.
A spokesman for Immigration Minister Michael Woodhouse said the scheme would lead to more new houses being built.
"We are conscious of the housing market concerns, and that's why to be eligible, investors need to be building new housing," he said.
"They are also excluded from living in these new dwellings."
He said the investor policy had been extremely successful in providing economic stimulus and bringing hundreds of millions of dollars in overseas capital to New Zealand.
Michael Yong, a Malaysian-based licensed New Zealand immigration adviser, who spoke at last weekend's seminar, said more than 10 participants expressed interest in migrating and investing.
The seminar was part of a New Zealand property exhibition promoting the Kingfisher lakefront development in Taupo. Posters promoted the development as prime waterfront land with "bungalow plots" ranging from 650sq m to 2322sq m.
"No stamp duty, no capital gains tax, completed development titles available today," it said.
Lois Lim, who attended a migration seminar in Singapore in January, said it had also promoted property investment as a pathway to New Zealand residency. She believed this was because Asians were generally more comfortable investing in property than in businesses, especially in markets that were foreign to them.
"With real estate investment, you own something tangible and the risk is lower," said Ms Lim, a Singaporean trader. "Of course it is really attractive if you can make money and also gain permanent residency."
New Zealand Property Investors Federation vice-president Terry le Grove, said this would drive up demand for land, and "there's already enough demand".
The rules
To come to NZ as an "investor" an applicant must:
• Be 65 or younger.
• Have a minimum three years' experience in business.
• Invest $1.5 million in New Zealand for four years.
• Meet health, language and character criteria.
Source: Immigration New Zealand
