Gary Hussman was on the property getting his RV fixed when he noticed something was wrong.
"Probably about 20 feet higher than the building, except for when it exploded, then it was 30, 40," said Hussman.
The fire began in the auto body-paint shop. Investigators say an RV inside the building started smoldering.
Employees tried putting it out with an extinguisher but it was too late.
"All the explosions started the propane tanks, the fire coming out melting everything in the building, it was too hot for anybody to get close to it," said Hussman.
More than 30 firefighters worked together to successfully contain the flames to the building. There were many challenges.
The engines had a hard time maneuvering inside the tightly packed dealership. There was also low water pressure and combustible material.
"This is a mechanic shop, so there's a lot of hazards firefighters are dealing with. Most of the content will be a complete loss," said Cal-Fire Fire Captain Jeremiah Whitter.
The damages will likely total several millions of dollars. Firefighters have not been able to make it inside yet because the building is so unstable.
"They got to do what they got to do, then they can worry about us, they've taken care of us," said Hussman.
The business has served Valley customers for decades and tonight, customers say it is their time to show support.