Machine Learning: Process

[jefsummers]

So, what are you trying to maximize or minimize? Unused cars, profit at each location, what?
If profit, how do you calculate profit (hint, revenue minus costs)? What are the costs? what are the revenues? Do they vary day to day?

If you are wanting to model, then what are your dependent and independent variables?
Answer that, and you can start. Note that you will want a regression type rather than classification type model if you choose to go this route.