Mr Freeman began organising them as fundraisers for cancer societies as he lost both his parents to the disease.
They have since raised more than $6.1 million for the Cancer Council in Australia - making it the largest independent fundraiser.
"I hope we can mirror those results in the land of the long white cloud," Mr Freeman said.
That ambition was well on the way to being realised with $370,000 having already been raised for the Cancer Society here.
"The plan is to get more Kiwis involved so we can run it annually, and maybe incorporate the South Island."
Ten of the participating 62 teams are New Zealanders.
"We're excited about bringing it across the Tasman and I have to say, this has been the best road driving I have ever done - it is so much different to what we are used to in Australia and the scenery...unbelievable."
Mr Freeman said judging by the imagination and decorating skills of the participants the vehicles would be noticed, despite not staying in one place long.
There are two people to each vehicle and they are well into the 2550km expedition in the name of raising funds for the New Zealand Cancer Society.
The society's chief executive Claire Austin said she was delighted to have been approached by Mr Freeman and to be part of it all.
"Cancer is the leading cause of death in this country - funds raised will help us continue research."
Clearview Estate Winery at Te Awanga was also on the "give them a call" list as the Australian-based organisers sought somewhere for the fun fleet to stay overnight.
So the winery folk got in touch with neighbouring OutFoxed who were happy to host the cars and participants overnight.
The winery was also hosting the participants for dinner tonight and an early breakfast before they hit the road north to Rotorua, then Tolaga Bay, Opotiki and back to Auckland on Friday.
Each rally supporter had to raise a minimum of NZ$4500 to qualify to take part, and along the way the fundraising continues.
Once they collect the qualifying sum they are provided with a very modest cheap car and away they go.
"It's a lot of fun and there is a lot of great camaraderie," Mr Freeman said, adding one team had already fundraised $29,000 alone.
Of the old cars, there were always "a few issues" he said.
Some of the team names say it all. Bare Grills, Are We There Yet?, Dragon Wagon, Bucket List, Loose Nuts and Mums on the Run.