I don't think the website is the most reliable way to get the information you're looking for.
Here's how most builders or homeowners get their quotes for either new houses or additions:
1. Employ an architect or home planner (you could actually do this yourself as well, depending on the complexity of the remodel) and get drawings on paper and to scale (or with measurements).
2. The drawings on paper give you and whoever you are consulting with, the language or visual, showing them exactly what you want, and with the needed detail.
3. Once you have the drawings, take them to lumberyards, maybe Home Depot or Lowes, and your builder to get quotes. If you can't decide what builder you will be using, have each of them give you quotes. You will leave a drawing with them. If you want itemized lists, ask them if they can do that for you. This would show a break down of approx. costs per room, or however they itemize it. You will leave a drawing with them and come back later to pick up your quote or have them email it to you.
4. Always get at least 3 quotes. Remember these are just quotes and are by no means the final cost. Each of the builders or lumberyards know you are looking for best price, so they are all plugging in the very least expensive products, also called builder quality, into their quotes which means if you want better than that, then you'll need to go in and add individual costs of items you are upgrading.
5. The general rule is to not go with the cheapest quote or the most expensive, but pick one in the middle.
6. Then when you're all done, add 10% to the overall cost.
This is the kind of work you, or anyone else, needs to do to get closest to a final cost. And it still won't be the final cost of the remodel, it just gives you a goal to shoot for. This is something that you'll not find on the internet because each project is just so different.
It's possible that you could go on your local home builders organization website and find some useful information there. You could also find a builder that way too. Usually, the older guys that belong or are members of the organization have been guys that take their work seriously and are committed enough to be part of the local organization. Just google "home builders association" in your area, and you'll find their website.