The building is still standing but Miller's Air Conditioning and Heating, which has been in business for 46 years, was destroyed.
The owners have no digital backup of any of their records.
"We are all paper. We have nothing on computer yet. We were just starting to implement that. Then this -- it's going to be a little rough," shop foreman Mike Legate said.
Firefighters got the call around 11:45 p.m. on Tuesday.
Millers air conditioning in Livermore caught fire late last night. Firefighters will look for cause this morning. pic.twitter.com/yuQSfeXJLk— Amy Hollyfield (@amyhollyfield) July 13, 2016
When they took a closer look on Wednesday, investigators decided the fire looked suspicious.
"What makes it suspicious to us is just the time of day it started, we don't have any witnesses that are telling otherwise and we don't have an obvious cause and origin," Livermore-Pleasanton Fire Department Dep. Chief Joe Testa said.
Officials will look into whether the fire started there and then spread to the business.
The fire was so big, they had to stay on the outside. Shortly after they arrived, the roof collapsed.
"It's horrible. We are gonna keep going through, we're gonna start over. It's gonna be good," Legate said.
ATF investigators are on the scene. However, we were told not to read too much into that, that they often come out to get field experience and also to train local firefighters.
ABC7 News has tried to contact Livermore police to find out who they think could have possibly set this fire but they haven't responded yet.