Real Estate photography does not come "right out of the camera"; Each home is different in the sense that each has its own challenges when it comes to light, shadows, colors, unwanted objects, and weather too. Our job is not to make homes look unrealistic, but our cameras cannot capture a space as it is unless we use extra lights, and even then, there will still be editing left to do. Unfortunately, we don't always have the luxury of time to bring and use the extra lights needed, so we have to use photo retouching techniques in order to achieve a pleasing, and realistic result. 
Below are a few examples of images I retouched for my clients. Not all images are in need of major Photoshop surgery, but each image needs something to make it appealing to a potential buyer. I was asked to simulate sunset, replace paint chipped because the homeowner couldn't paint the home "before" the photoshoot, so they gave me the paint color to repaint the home in Photoshop (4th image down), remove yard signs, and many others. Most clients ask to have street wires removed. This is a very popular request, and something we really cannot avoid, as is with sky replacement. We can't control the weather either, so we are grateful for Photoshop allowing us to turn a rainy day into a sunny one! 
I have re-touched images for other photographers too, and unfortunately in most of those cases they sent bracketed images meant for HDR editing. ((HDR means High Dynamic Range - meaning capturing mid tones, highlights and shadows by shooting three different images). The problem is that by "just merging images to HDR"  we will not be able to re-create the correct colors and light the space/room had in reality, and that ends up deceiving a potential buyer. HDR is not an extra light source, and usually it has really big trouble managing reds/oranges, as in oak type cabinetry, and dark or black furniture.