I’m student of architecture and i find Blender very interesting, but I don’t know if it is the right choice for me. I’m new in community. I don’t know if the Blender is such accurate for designing buildings.
Blender supports PGM (precise geometry modeling), it shoud help working with exact sizes, after that (via Swift 3D) you can export all your’s project to Illustrator and make a tach-draws, it’s possible to make real time presenations to you’r building’s or whatever, it’s best 3d software in the world, and your cheef’s eye’s will be cubic after he will find out that software (where you made all those buetifull buildings) is free.
So use ArchiCAD and never ask again questions like : " Is blender good for mee %| ?"
Thanx 
Things just happen to be going your way:
http://projects.blender.org/projects/blendercad/
http://www.blender.org/modules.php?op=modload&name=phpBB2&file=viewtopic&t=1316&start=30
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