The man collected over 7500 cars throughout his lifetime, starting when he was about 6 years old and continuing until his recent death in his 80s.
Proctor Auctions owner Ronnie Proctor said he had about 5000 pieces of the collection, and about 700 lots would be up for auction on Sunday.
The collector’s family had already sold about 2500 pieces on their own.
"A lot of these are early-mid-1950s to 1960s ... and some are from even earlier when they were still called Moko."
The collector had not stopped at the older cars, collecting some of the newer ones as well, Mr Proctor said.
There were entire sets from the early and mid-2000s.
"There’s some here that are fairly quite rare and valuable — he was collecting for a long, long time.
"It’s been a big labour of love for him."
Matchbox cars had been displayed in every single room of the man’s home.
The truck was loaded top to bottom with Matchbox cars, he said.
For most of Matchbox’s history, the United States and United Kingdom got the standard black and brown model cars, whereas New Zealand and Australia got the more unique variants.
That fact usually drew a lot of overseas collectors to this corner of the world, he said.
"I’ve had phone calls from the US, England and Australia ... at all hours of the night."
While over 700 lots were listed on his website for the upcoming auction, there were still mountains of Matchbox-filled boxes waiting to be sorted in the back of the store.
"Every couple of months I’ll bring in another load of cars and do another auction."
Mr Proctor said he thought he knew "a fair bit" about Matchbox cars until he took on the task of organising the collection for auction.
He had learnt more than he ever thought he would in the process, he said.
"It’s been really eye-opening sorting this all out."
