I have an assignment in a couple of weeks to PM a building. I'm wondering what lens will be best for a Canon 5D camera. Is a fixed focal length more accurate than a zoom? Is wide angle better/worse than telephoto? Any suggestions for the best way to photograph this would be helpful!
 
-Steve
3dlidar.com

It's better to use a fixed focal and as it's buildings a mid wide angle will be best.

Wouldn't a long lens give you less distortion?

Yes, but you'll have to stand further away. Also, IM will remove the distortion in the image.