Hi Ceciil

may I ask if having a toilet in the middle of the house really bad fengshui? How can we tell if the toilet is indeed in the middle of the house? For example, this floor plan here. 

1. Yes, technically the toilet CAN be considered at the centrepoint of the unit:-

2. A consolation is that at least, it is not the WC.

3. Often, one concern or issue does not "sink a ship".

4. It Depends! Hopefully this unit is not at the bottom rung of the bell curve.  

5. Case Study: Do you know that even if a geomancer says that the site is excellent, all sites are govern by the concept of the Bell Curve

5.1. Remember, even if a geomancer says that this is a good development. However, a good unit also depends on where it is within the development:

5.2. Is your potential unit under the Good, the Bad or the Ugly?

5.3. Often if one is lucky, even if the unit is not so fantastic superficially. Some units are like an unpolished gem. While others unfortunately may be a hopeless rotten apple.

5.3.1. Just imagine, if the unit is like a 10 year old rundown 1,000 cc car. Even a good Feng Shui Master is unable to turn it into a good unit!  

6. By the way, (above) this falls under Habit Number 11.

7. Under Habit 1, one possibility is by ranking one's bedroom type by stack/unit: 1st choice, 2nd choice etc... 

Reference: Habit 1 can be found under this link:-