It is all real, but yes, it is photoshopped. That's how I do my work. It's called HDR. I take several photos at different exposures of the same scene. This makes it possible to pull the window views, and it also makes it possible to show dark corners as well. I also have another handful of steps specific to my style and technique.
I do, however, disagree that anyone can take a great photo of a great house. Even the most expensive camera's, and best lenses in the hands of someone who doesn't know what they are doing, can not create a great photo. It takes a lot of time, and attention to detail. I spend about 5 minutes actually taking each photo, and then I spend about another 30 minutes to 1 hour bringing it to life in photoshop. It is not possible to capture the caliber, and quality of photos that I do, by simply clicking a shutter.
As for poor houses, I would be able to take great photos of those as well. Of course I could not make the homes be as nice looking as million dollar homes, but the quality of the actual photograph would match those of the million dollar homes.