Trying to create 3D model of van

Hi! I would go the route of box modeling or splines using a reference inside of , where you construct on top of an image. Then mirror, attach vertices and smooth for the end result.
Here’s the approach of making a building using the above ideas. Just adapt these techniques to what you are trying to achieve.

://cgi.tutsplus/tutorials/modeling-from-photographic-reference-in-3dsmax–cg-5327

And splines in

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