As someone who is adding whole house audio to my current house, I will say to at least wire every room in the house you may ever need including any hallways for future needs. Don't skimp on the future wiring and rough in Cat wiring. Accomplishing this in an 'old' construction has to be easily a hundred times more difficult. I would have at minimum two speakers in the kitchen/nook, the dining room, the study, stereo (dual voice coil) in the hallway and two speakers in the master bathroom as well. I would wire in the garage as too. It is so fantastically difficult to accomplish this in an old construction, If we ever build again, I will rough in every room in the house I think. As for speakers, I am doing my whole house with substantially less costly Monoprice speakers both 2 and 3 way versions all 8" and round ceiling and rectangular inwall while the main seating area I did on-wall Energy speakers and a sub. You really have so many open ended questions. With a properly set up whole house system, you wouldn't really need more than one receiver. There are multiple ways to distribute whole house audio and it comes down to control and money. You can do the cheap way that is now possible because of the fact that AVR's now have WIFI apps that can control a lot of functionality anywhere you have a tablet or phone or ipod/android device of the more expensive way with key pads in each room or zone and the more costly components involved.