Mr Bell was last seen at his Dallington home on Thursday morning.
Detective Senior Sergeant Archer said police were still making inquiries into Mr Bell's background for clues to his death.
He was a self-employed car salesman, who bought cars off Trade Me, repaired them and re-sold them.
Bullet holes found in the side of the car were not related to Mr bell's death, or the fire.
"A group of recreational shooters came forward and told police they were in the vicinity on Friday evening. They have indicated that the car was already burnt out at that time and they fired shots at the vehicle using a rifle," Detective Senior Sergeant Archer said.
Police have spoken to Mr Bell's family and partner who were "extremely upset and are trying to come to terms with his death".