The proposal to increase stamp duty on vehicles over $100,000 has drawn criticism from regional workers who say their work utes and trucks aren't a "luxury".

"If there is some inherent unfairness in it, of course we are willing to sit down with people and remove that unfairness," Mr Daley told reporters in Kingscliff on the state's north coast on Thursday.

"If we have to do something to exempt farmers from that, for working vehicles, we will."

Transport Minister Andrew Constance, who represents the agricultural electorate of Bega, said Mr Daley was waging "class warfare" against farmers and regional Australians.

"What we can tell him is that farmers do require dual-cab LandCruisers to run their farms and run their work staff around," he told reporters in Sydney on Thursday.

"We can tell him the farming community needs government off their backs at a time they're suffering enormous drought right across regional NSW."

Despite conceding he's willing to reconsider aspects of the proposed tax, Mr Daley doubled down on the fundamentals of the revenue-raising measure that Labor will use to pay for more nurses.

"If I have to increase the stamp duty to people who are millionaires, then so be it. I make no apology whatsoever for that," he said.

"If we want to have these new nurses, 5500 new nurses ... we need revenue."

But when quizzed on the intricacies of his new tax, which also applies to boats over $200,000, Mr Daley couldn't say whether it would apply to tractors, headers and other farming equipment.

He later confirmed the policy would not apply to them. He said he remains open to reconsidering "limited unforeseen consequences" of the tax.

NSW Treasurer Dominic Perrottet attacked Mr Daley for failing to be across the detail of his own policy.

"What we've seen from Michael Daley is shooting from the hip with undeveloped policies and when put under pressure, he changes his policies," Mr Perrottet told reporters in Sydney.

"To have a policy where you are taxing farmers in the middle of a drought speaks volumes of the Labor party's policy development."

The state opposition leader was on Thursday touring the battleground seats of Tweed, Lismore and Ballina, where tight contests could decide the outcome of the March 23 election.

Premier Gladys Berejiklian toured the region on Wednesday, where the coalition is fighting to hold on to both Tweed and Lismore while also trying to win back Ballina, which the Nationals lost to the Greens in 2015.

The premier met with farmers and tradespeople near Lismore, who said the increase in stamp duty could cost them thousands of dollars for vehicles they relied upon for work.

Australian Associated Press