Police are scouring car wreckers, cell tower records and CCTV footage in the search for missing Auckland man Denver Chance.
The 43-year-old was last seen on the afternoon of Sunday, 24 February, when he told friends at his flat in Mairangi Bay on the North Shore that he was popping out and would be back soon, but failed to return
His red Nissan Skyline was last seen at 4.17pm on the southern motorway near Drury.
Police initially said his car was seen in Waihi disappeared but now say that may not have been the case.
They say its possible another red Skyline was spotted in Waihi, and the quality of CCTV footage means it's not possible to read its licence plate.
Detective Senior Sergeant Megan Goldie said police were still carrying out inquiries in Waihi - and nearby Waikino - because Mr Chance was looking to buy property in the area.
They were also looking at Karaka, in rural southern Auckland, because phone records suggested Mr Chance was in the area the day he went missing, Ms Goldie said.
Police are now checking car wreckers in the Auckland region in a bid to locate the vehicle.
Ms Goldie told Checkpoint all police could conclusively say was that he was last seen leaving his house at 3.30pm and walking up the driveway.
"We don't have any confirmed sightings of him in that car. We have the car on the motorway and heading to the motorway, but no actual footage anywhere where we can conclusively confirm that he is in that car," she said.
"It's an assumption that he's driving that car."
But she said no one else drove his vehicle - he kept his keys in his room - and there was only a very "slight possibility" that someone else met him up on the roadside and drove off in his car.
Ms Goldie said Mr Chance's cell phone pinged a cell tower in the Karaka area west of the southern motorway on the Sunday. He has not used his cell since he disappeared.
"We just really need to establish where he's been, or where his phone has been in those hours in between the sighting on the motorway and then the pinging in the Karaka area on the cell tower."
His mother, Paula MacGregor, told Checkpoint that his family, friends and their helpers have been looking everywhere they can - checking roadsides and scanning possible routes.
Ms MacGregor said Mr Chance had rung her at about 2.30pm the day he disappeared to say he was going to visit her that night but she had plans so they rescheduled for Thursday.
"We left it at that and I don't know any more until I've heard from his flatmate the next day just asking me 'had I seen Denver', and I said 'no' and it's just gone from there."
She said he seemed "perfectly fine" on the phone, and his flatmates also said he seemed normal.
It was out of character for him not to contact his family like this, Ms MacGregor said.