I'm building a new home. There are several things I want to do for whole house sound, but I'm a new to home theaters. I have 1 room which will be the media room, I'll have 5:1 surround sound. I'm planning to put in-wall speakers in there. Then I'll have 2 rooms and the patio which will have 2 speakers in each spot/room. I would like to have volume control in each room. I'd also like for all the speakers to be run by 1 central receiver. So I think this means I'll need an impedance matching box. The only thing I plan to do is use it for DVD,VHS and CD. Given this description, what should I look for in a receiver? What questions should I be looking to answer?