"Produce CDs that sit in the CD player of rental cars so that, when a new driver gets in, the CD can tell them about the car, the local area, driving laws, etc. It could also feature advertising for local businesses." Would you invest in this product idea?
Well, the idea sounds fine to me.
CD will give most of the information the consumer needs and, possibly, advertise some local businesses. The information about the car or local area will save the time of people who work for this rental company, which means they will be able to increase their productivity, therefore, have more cars rented and increase company's profit. The information about driving laws or, for example, safety rules, will decrease the possibility of an accident which means less spenditure on car fixing. Finally, local businesses will pay for advertising on these CDs, which means more money earned by the rental company.
However, we can't be sure that consumers will actually listen to CDs - they might just remove it from their CD player and put there some music or audiobooks.
Actually, I wouldn't invest in this idea, because I'm not so close to car rental businesses and I might not now some details of this market.