We got ours from Romac, the garage door people. We have the sliding kind which cost under $700 for a two car garage. That's with the upgraded white privacy screen. We actually paid less for the two car garage screens than we did in spring 2007 for a 1 1/2 car garage. Guess the slow economy has reduced the price.
Yes, they can be a pain to have to move back and forth but we think, for the price, the benefits outweigh the inconvenience. Our garage is well ventilated and cooler, we don't have to worry about "critters" coming in the garage, and our neighbors across the street get a nicer view rather than "the ugly open garage look". I'd recommend them!