What’s the product? One seat? Two seats? Coupe, sedan, van, pick up?
Just make sure it has a device for connectivity. That’s seems to be most current consumers care about. Look at what cars people are buying today and what they’ll be buying by the time you turn twenty.
Automatic transmission, seats four, fits two to four rolling suitcases, easy to get in and out for a woman of about 5’4”, easy to adjust for driver comfort, power windows/door locks and all the driver safety aids. Time and mileage length of factory warranty. The longer the better, in both categories.
Honestly, if I were your age today and wanting to do this(I was and wanted to design cars), I’d be door knocking at Toyota. Looking at their(and their partners) kei car segment to get a foot in the door.