The fire destroyed four of Mr Russell's personal classic cars which he had spent years restoring.
There were also five clients' cars, a new jet boat and two racing cars in the burnt-out building.
One of the race cars belonged to a friend of Mr Russell's and was due to be painted yesterday.
"It's still sinking in," he said.
"The worst part was the two cars, the 1951 Cadillac and 1962 Ford Thunderbird - they're irreplaceable," he said.
He had insured the cars when he first got them, but after restoring them for the past five or six years they would be worth a lot more.
"I'd say their worth around $50,000 or $60,000 each."
Mr Russell said he didn't know how the fire could have happened.
He said "the boys" had locked up the building where the fire happened at around 5pm. Mr Russell had returned to the building at quarter to six and everything was fine.
"I was there only an hour later and nothing was smouldering or anything."
Hastings Area Commander Chris Nicoll said when fire services arrived at the scene around 11pm last night the building was completely involved.
The volunteer fire service had been battling the blaze, but it was so severe fire trucks from Hastings, Napier and Havelock North were called to the scene.
Mr Nicoll said they did an "external deliverance of attack" so no firefighters would have to enter the building because the risk for them was too great.
More than 30 firefighters worked together to get the fire under control, and had it contained by 1.30am.
Fire Safety was carrying out an investigation into how the fire started, but Mr Russell had been told early signs were pointed to an electrical issue at fault either in the building or with one of the cars.
They were not treating the fire as suspicious.