Simon Bridges is pledging to make sweeping changes to housing rules if National were to win the upcoming election.
On TVNZ1's Q+A, he told host Jack Tame he would reverse Labour's changes to ring-fencing losses, which no longer lets landlords offset residential property deductions against other income.
National would also "by and large" reverse the Healthy Homes standards, aside from insulation rules, that include the progressive introduction of standards such as extractor fans in bathrooms and kitchens.
"I think the problem is they have increased the cost for renters," he said.
Mr Bridges said he would not change the insulation rules.
On high house prices, Mr Bridges said the "the reality of what we can do is stem the rise that we have seen for some time".
"The way to do that is bold, significant RMA and land reform."
Mr Bridges said he would allow foreigners to buy homes, saying there was "a happy medium between where we were in the past and where this government is".
He said he would enact that by setting "values on what you would and wouldn’t allow".
Mr Bridges also said the former National Government was "two years too late in terms of what we did" for housing, but "had the right policies".
Watch Q+A with Jack Tame on TVNZ1 at 9am on Sundays.