Two cars located in the parking lot of the Avis car rental, located at the corner of Langelier and Lavoisier boulevards, were set on fire sometime just before 2 a.m.
A third car was also damaged.
Montreal police Const. Anie Lemieux said investigators are looking into what links may exist between the latest incident and the previous two fires.
"That's what our arson squad investigators will be answering in the next few hours, few days," she said.
Police have not identified any suspects.