I recently purchased a trailer, which had a cancelled registration (last registered 10 years ago). The purchase was all above board. I purchased it from a guy that refurbs trailers as a side business. He showed me some of the frames of other trailers he was refurbing.

The trailer has a WOF that is valid until the end of the year, but no rego. What I didn't understand at the time of purchase was that the transfer of ownership works differently if the vehicle is not currently registered. I said to him at the time that I would sort out the change of ownership later that night. If it were a car, I would have done it on the spot.

My understanding is that it's now on me to re-register the trailer, but I'm having difficulty understanding what the process is. The NZTA website says I need sufficient proof that I should own the vehicle. The only real proof I have is the Trademe auction that I won. The seller isn't very responsive to my emails, but that isn't unusual for him.

What would be my best next step?