The key to solving this mystery is in considering where the body was found.
Jane, Zsa-Zsa, Flora and Hercules all claim that the last time they saw Kurt he was under the bus tinkering with the engine. Yet his body was ‘found’ by Garrick inside the bus and it was far too bulky to have been moved after death. Is it possible that Garrick killed him there and then pretended to the police that he had stumbled upon the body?
Throw in Jane’s evidence about the insurance policy and Garrick’s problems with his creditors and you also have a strong motive.
The murder weapon may have belonged to Hercules but the fact that the handle had been wiped clean of fingerprints only weakens the case against him.
As many of you deduced, Garrick McBranagh was the real murderer!