Liam Watson killed Miguel Reynolds – who went by the stage name Lil Gwop Boy – after a plot to rob him went wrong.
The 32-year-old had told his 21-year-old victim he would sell him the Audi S1 for £2,000 during a series of conversations through intermediaries, a trial at Liverpool Crown Court was told.
But when the younger man, from Moss Side, turned up in Liverpool’s Netherton area on 7 June 2018, he was met by a gang of men who took his money then told him he would not be receiving the car and ordered him to leave. One was armed with a pistol, thought to be a Glock.
When Reynolds - who himself had a knife - gave chase, Watson shot him dead at point blank range, the Liverpool Echo reports.
The killing – described by prosecutors as like an execution – was witnessed by a pensioner, who later died.
"Oh God, I can't even breathe watching this,” Joyce Lennon told a 999 call. “I think somebody has just been shot a few yards away."
Watson, 32, of Litherland Park in Litherland, was found guilty of the murder on Tuesday.
Six other men were cleared of murder but one of them, Kyle Sanders, 22, of Charles Best Green in Netherton, was found guilty of manslaughter.
Both will be sentenced at a later date.