Ed,
I echo ad!
You are looking at a very complex project and it is so complex it would be impossible for me (someone else might be able to talk you through the project however I can't) to point you in the right direction. Depending upon the home the layout what the room looks like how much head space you have how much available run you have how many treads you will need ... and the list goes on and on. To top it off there is a banister with balusters and handrails turnouts goose necks etc that complicate it even more. This is a project that would be tough for an entry level carpenter and would definitely be a fairly significant project for a seasoned professional carpenter to tackle.
I thin the first question that was presented sums it up best do you have a lot of
1) tools
2) skill
3) patience
If you have those three then you probably would not be here. I would advise you to hire this project out to a very experienced carpenter as the components to this project are expensive and a person does not want to practice or make this a trial run unless you have plenty of money and a good sense of humor.
Good luck and be safe!