What's the deal with the Australian first home buyers grant? Do you have to be an Australian Citizen to get it?
If you are a NZ citizen, you are eligible for the first home owners grant as long as you or anyone else buying the house with you hasn't had the grant in the past. Also, be aware that if you have owned a house anywhere in the world (including NZ), you will have to pay stamp duty. This is the fact for QLD, but different states might differ, so check it out. In QLD, it is 1% of the houses value up to $320,000 then it goes up.
what is stamp duty?
Stamp duty is another government tax - it's a way they make money from all the real estate deals going on.
can you get this straight away or do you ahve to wait for four years?
You can get it right away, if you are eligible. It has just been increased to a maximum of AUD$26,000, depending on which state you live in. See here for more info: http://www.firsthome.gov.au/
New Zealand Citizens are eligible to get the first home buyer's grant. You just need to be living in Australia when the eligible transaction is completed.
https://www.sro.vic.gov.au/first-home-owner/applying-first-home-owner-grant