Sometimes I use 3D for creating buildings, but generally only for complex structures that aren't easily done in vector or image editing. Probably use Sketchup. Creating buildings is rather simple and straight forward.

However, most buildings are pretty simple to do. Attached is an illustration of the steps I do to create photo-realistic buildings that "pop out" in my maps using Xara Photo & Graphic Designer 9 (a vector drawing application), but the technique can be done in most vector or image editing applications, including Photoshop/GIMP/Illustrator/Inkscape.

GP

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