AE Compositing (Roto, BG Replacement, Camera Track) about 2 minutes

I have around 20 clips of video (720P, 29.97) each is a few seconds and the total duration of the project is approximately 2 minutes. Clips are from a low budget music video displaying a female singer singing in a room in different poses. I'd like to have the backgrounds of the clips replaced by tacky cracked dirty walls and a window. So the clips needs rotoscoping, tracking, and editing and compositing the new background. My VFX artist had an emergency and had to leave the country. He has done 90% of the VFX done and this 2 minutes is the remaining 10%. I will provide you with samples and the needed material as much as I can to make life a bit easier for you! I don't want the room to be designed and created in 3d, I just want the walls to look like the rest of the project, so you might want to do these changes on the actual walls without even removing and replacing the backgrounds. It is up to you and your skills. You'll see the samples and tell me what you think. One important thing, when bidding please bear in mind that it is a low budget project. Thanks