The changes come ahead of plans by the new Labour-led government to clamp down on foreign buyers.
Under its agreement with New Zealand First it will ban foreigners from buying existing homes.
Lu said any new restrictions could cause buyers to bring forward purchases they were planning to make in the next year.
"We saw the same thing happen in Vancouver, Melbourne and Sydney when new taxes and restrictions were introduced.
"One premium buyer in Sydney closed his transaction 15 minutes to midnight before the new regime kicked in."
Auckland remains the most popular city for Chinese buyers followed by Christchurch, Wellington, Queenstown and Hamilton.
Lu said three-quarters of Juwai.com's buyers in New Zealand said they were looking for property for their own use, either as a first or second home.
"About one fifth are purchasing a home for a family member to live in while studying in New Zealand."