I created several models of cars according to blueprints. The original purpose was to create an asset to my game mod (see the Audi Q7 model at the very bottom). Later on I needed a car models for my architectural projects, but I didn't want to buy one, so I tried to create my own (and practice modeling at the same time). So I created a few more car models (Audi A3 2008, Škoda Superb 2007 and 2019).

The process is the same: set up a scene with a reference blueprints and get a lots of reference photos. The models have no interior and contain a few geometry errors. But these don't matter because I use them in my architectural projects where they are just props, so the errors are not visible.

My first car model attempt of Audi Q7, created in 2016. It doesn't look like a reference or real car, but at least I learned some modelling and modifier stacking techniques.

Rendered in Cycles

Details made mostly by mind

 From ortographic renders I manually created texture so it fits to UV map (I did it manually, because I didn't know anything about texture baking at the time)

Final lowpoly model ported in Half-Life 2 Source engine