Ya got to give us more then that!
Where's the fixtures located? Slab? First or second floor? Where? How close is the nearest 4" pipe?
The water's easy but drainage can present a problem. Different locations will have different problems. Give me all the details in your next post.
You ask how easy? You're talking major surgery here. Unless you have plumbing skills and tools better to contract the job out. Good luck, Tom