English: I spoke with the owner and she said she really liked the way the paint changed color depending on the light and view angle. She was proud of it and that seems like an obvious reaction. Pretty car!
Inspired by S. Herschel, below, I made a study of Tesla door handles. The exterior door handles are the easiest way to tell the S, 3, X and Roadster apart. Model "Y" are derived from Model "3"
Model S has trapezoidal external door handles, parallelish top and bottom with non-parallel, indeed, not straight, front and back ends. The ends are a combinations of a straight line and a curve, with the straights at different angles to each other. Each Model S door handle is toward the aft edge of its door.
In contrast, the Model X has the handle of the front door at the back edge of the front door and the handle of the back door at the front edge of the back door. The two handles make a single, elongated, trapezoidal shape- with very strongly parallel top and bottom. The front and back handles are divided vertically, at the gap between the doors.
The Model 3 has exterior door handles something like a smoking pipe - The long, nearly horizontal, part slopes down toward the front of the car. The rear 10-16 % is taller. The effect is somethng like: ":::::::::::::::::////". with left to the front and right the rear. As with the Model S, each door handle is near the back edge of their respective doors.
Model Y and Model 3 have the same handles (Y's are derived from 3s) but the Model Y rear doors' rear edges overlap the rear wheel arches. Model 3 rear doors look more like Model S rear doors.
The Roadster can be easily recognized because it has only 2 handles, and only 2 doors.