KiwiBuild is once again under fire, with National saying the latest revelations once again show it is helping out the middle and upper classes.

Housing Minister Phil Twyford has fired back at a RNZ report, based on an Official Information Act request, that someone who could raise up to $650,000 for a house deposit would still be eligible for a KiwiBuild home.

This was based on data from 500 pre-approved KiwiBuild applicants.

The data showed 16 applicants declared deposits of more than $200,000, with a number of others declaring more than $300,000 – the KiwiBuild unit told RNZ that three people said they could raise $650,000.

Speaking to reporters this morning, Twyford said the data was "raw" and "error-prone" and accused RNZ of "willfully misrepresenting [the] data".

"[The data] is basically compiled from information that people have entered at home into a website questionnaire."

He said in one of the cases, where someone declared a deposit amount of $570,000, that same person purchased a KiwiBuild home with an $80,000 deposit and a $490,000 bank loan.

There is an income cap of $120,000 per year for a sole purchaser or $180,000 if multiple people want to buy a KiwiBuild home.

But there is no such limit when it comes to how much the would-be buyer has in the form of a deposit.

National's housing spokeswoman Judith Collins says this is further proof that KiwiBuild is a welfare programme for property developers.

She told Heather du Plessis-Allan that $650,000 is a lot of money to turn up for cash, and that some of the homes in places like Wanaka are not beneficial.

"They'll be great ski lodges for your kid to put their name down for and you put up the money and now suddenly you've got 10 per cent off."

Collins has rejected Twyford's denial, and says it is a "cock-up" rather a conspiracy. 

Twyford said it has never been the policy of the Government to have an asset or means test when it comes to KiwiBuild.

He said if people want to get deposits from their parents, relatives or friends, they are able to do that.

He called Collins out on her criticism and said that under the previous National Government there was no means testing for any of their first-home buyers policies either.