A surprise collection of 1,300 lots of Holden and other memorabilia, including 120 cars, secreted away by a South Australian panelbeater has gone under the hammer at Cummins on Eyre Peninsula.

Key points: The Cummins panelbeater accumulated thousands of Holden parts, vehicles, and other motorbikes, enamel signs and antiques in seven locations

The Cummins panelbeater accumulated thousands of Holden parts, vehicles, and other motorbikes, enamel signs and antiques in seven locations His daughters called in the experts to determine what was valuable after already crushing 180 cars

His daughters called in the experts to determine what was valuable after already crushing 180 cars An auctioneer says the value of some Holden cars leapt 10 per cent when Australian production ceased, then 10-15 per cent per year

The auction, which ended on Sunday, was a Holden fan's dream with thousands of parts on offer, including an original grill badge from a 1948 FX Holden — the first model ever made.

The Holden parts, vehicles, motorbikes, enamel signs and antiques were the collection of Cummins' only crash repairer Terrence 'Skippy' Skipworth.

But when the 59-year-old recently died of a heart attack, his three daughters did not know the extent of the treasures he had tucked away in work sheds spread across seven properties.

When they opened the doors they discovered a lifetime of memorabilia.

Mr Skipworth's daughters Rebecca Whillas, Simone Murnane and Jenna Skipworth remember he was always tinkering around with cars.

"He just loved Holdens. He'd go to swap meets as far as you could go to get certain pieces he was after," Ms Murnane said.

Skippy, pictured with the FJ Holden that the family will keep, amassed thousands of Holden parts over a 35-year career as a crash repairer. ( Supplied: Rebecca Whillas )

"We had them in the driveway as kids, the car port, and then the collection just grew. We didn't realise how big it was," Ms Whillas said.

"I think it's actually bigger than Dad would have known. He'd buy stuff and then hide it away or keep it locked up. He would have not known half the stuff he had," Ms Skipworth said.

"His plan was to have a pair of each series of Holdens, and then he could mesh that together to create a good one."

Sisters Simone, Rebecca and Jenna on the antique truck their father Skippy would drive in the Christmas parade each year. ( ABC Eyre Peninsula: Jodie Hamilton )

Mr Skipworth's ultimate plan was to retire and restore the classic cars, but he died before being able to restore any of them.

Home state's 'mind-blowing' collection

It has taken a year and a half to sort through it all and prepare the Holden parts and vehicles for auction.

"This is the biggest auction that Bennett's have ever done numerically over the 35 years we've been doing this," said Bennett's Classic Car Auctions owner Larry Bennett.

"It's just huge, and it's taken us ages to get it all together and to get it on the internet and up and running.

Auctioneer Larry Bennett says Skippy's auction was the largest collection of Holden parts and memorabilia to go under the auctioneer's hammer in SA. ( ABC Eyre Peninsula: Jodie Hamilton )

"With 1,300 lots, we had to rejig the internet program [application] to take it.

"It will be certainly the biggest Holden-themed auction in South Australia that I've ever known."

Mr Skipworth's daughters employed Mr Bennett a year ago to sort through the material.

"It was a bit mind-blowing when I realised how much stuff that they had," Mr Bennett said.

"The family were taking me around. The more they took me around, the more shocked I was."

Bennetts had to sort the vast collection into pallet lots rather than individual pieces, which still took three days to auction.

The auction house's owner said just about all the 120 cars listed for sale needed restoration, but the return on investment was well worth it.

"We had a 10 per cent jump in the value of old Holdens as soon as the factory closed a couple of years ago, and ever since we've had a jump of at least 10-15 per cent a year in the value of these ones. And they keep going up," Mr Bennett said.

Auctioneer David Weber said the collection was an iconic snapshot of Holden in Australia. ( ABC Eyre Peninsula: Jodie Hamilton )

"Some of the prices are getting astronomical, some of the collector's ones."

Treasure draws crowds

Holden buyers travelled more than 1,200 kilometres — some from Ballarat and Bendigo — to attend the auction.

Mr Skipworth's daughters said their father had often done the same, travelling interstate to go and get car parts.

"The auctioneers are very excited. To us they look like a bit of junk, but apparently they're sought-after pieces," Ms Skipworth said.

"There'll be some piece of metal and they'll say 'that's from a 1954 Premier'. We've just got no idea what any of the pieces were.

"There's things I didn't know were here — these almost-pristine leather seats from 1950-something Holdens, and the colours are amazing, and they were all locked up."

The daughters crushed about 180 cars before calling upon Bennetts to determine what was valuable.

"We don't even know what we are looking at, so we've had to have people say 'keep it, crush it, keep it' because we look at something and we don't know," Ms Skipworth said.

Simone, Rebecca and Jenna knew they had to get expert help to ascertain the value of the parts and cars before they trashed any more. ( ABC Eyre Peninsula: Jodie Hamilton )

"It is hard to see his favourite pieces go. We know how much he loved them and how much it meant to him, but it's not practical to keep them," Ms Murnane said.

"The sheer volume. I don't think any of us had any idea."

The sisters said they hope Skippy's legacy lives on in collections across the country.

"Hopefully a lot of these pieces will go on and be someone else's pride and joy," Ms Skipworth said.

"It's been a really, hard, long process, physically and emotionally," Ms Murnane added.

"We are wrecked."