In order to save some money, I have decided to tackle the wiring job myself.  Of course, I need to apply a permit for it, which naturally costs me somewhat (close to $300).  The previous owner has left an unused 40A cable in the crawl space, of which I can extend it to the new addition.  I calculate that 40A would provide 9600W and should be sufficient for addition.  Hopefully my calculations would pass the inspection.

I borrowed a simplified code book (2009-2011) from the library and start the work.  I know it is going to take me a long time to do it,but it would be a great learning experience.

Switch Box
I use ceiling support to make sure the fan would not fall.
Electrical boxes, cables, switches, breakers, receptacles.
The subpanel in the basement of addition.
Together with the plumbing, the 40A cable connects to the main panel through the crawl space and study room in a 6" plastic pipe.
8/3 cable that carries 40A of power.