Chroma keying (+video)

So I have been having a lot of issues on my set for my movie. I needed a white room, an office environment, everything needed to look perfect and I couldn't find any place. I decided to try using a concept called chroma key, commonly known as green screen. I have worked a bit with it, but nothing major. I do know how to use it and how to work with it in Adobe After Effects. I know it might be hard, but I am willing to make the effort to make it look how I want to. For people that are not sure of what it is and how it works, here is a little description and a video about it. Enjoy it.

CHROMA KEY
a digital technique by which a block of a particular colour (often blue or green) in a film or video image can be replaced by another colour or image, enabling, for example, a weather forecaster to appear against a background of a computer-generated weather map.