If you have some spare time available and would like to check out a great and long tutorial about modeling and rendering for architectural with Blender, I found a great reference for bathroom visualization created by Blenderpedia. The tutorial is all video based and has almost 4 hours in length, which could became really interesting for people trying to get all aspects of the process, but will probably be a challenge for artists looking only for the highlights of the process.
It is like I said; if you have the spare time. And if you don`t want to watch it now, mark as a favorite or bookmark the video for when you get that job involving bathroom visualization with Blender. Here is an image of the final result of the tutorial:
And here is the video: