We're building a house and I'd appreciate any suggestions to help with
my goals:

I want to purchase a system to use as the "main" system for the house
*most* of the time. I would like to use this system as the surround
system for the TV that we will watch most of the time also. I have
wired my house for five (5) pair of additional speakers (wall or
ceilings) throughout, and wired for volume controls on each.

I won't neccesarily need to run all five-six pair at the same time,
but it would be nice.

Will it be possible to run five to six pair at the same time?
I'm guessing I'll need to use some type on speaker selector box for
this many outputs?

I have not purchased speakers yet, either.

I do currently own an older Harman Kardon 35/w per channel receiver
that I can use somewhere.

One of the rooms where I have a pair wired for will eventually be a
gameroom/theater kinda room, where I plan to.... spend as much as
possible one day while yet avoiding divorce.

I think I can get away with about $500 on this "main"
receiver/surround/amp and remain married. Ideas on
receiver/speakers/controls????

Thanks in advance,
Steve in Louisiana