With that many windows you are either going to have to stay away from a projector or make sure that you include some creative ideas to block all of the light coming into the room. Projectors are really the best for large screens but have to have a light controled room.
What I meant by technical is does the thought of using 5 remotes scare you? Are you planning to do the install yourself?
I've found that most of my clients loved a multi-function remote to handle everything. It keeps it more user friendly and with discreet codes - you can rerun the command if it missed anything. With all of that said - I would go with a large LCD instead of the projector in any of those rooms. Some of the larger, higher end box sets might get you everything you want. The last install I did local on a smaller budget was around $6,500 and it included a 135" screen with screen goo (turned out nice), a Denon high-end receiver (still got one NIB from the install if you are interested), Denon DVD, 7.1 speaker setup (2 towers, center, 1 sub, 4 bookshelves), and a color touchscreen remote. The remote was 1,100 itself but without it the client had no hope of running any of it. Now, they just push (watch movie) and everything turns on and is set just the way it needs to be. Has more buttons for watch TV, listen to music, etc....
visit remotecentral.com for info on the remotes
visit monoprice.com for dealer direct prices to the public for all of your cables
Here's the best remote I've used to date:
Universal Remote Control Model MX-3000
There's some newer out there that I haven't used it yet but the MX3000 is awesome!
I've got an olderd Pronto black and white w/ rf extender and charger base that I've got for sale. all of it for $50. Might need a new battery when you get it - it's not been used since I upgraded the client to the MX3000