Thanks! The thing is I'm not sure we actually want to do it, it's potentially part of a larger building project. We've got quotes for the actual building work, windows, the hard flooring in the bedrooms etc etc. But I need and idea of the price of the carpet before we can decide exactly which combo of improvements we are actually going to do.
The carpet shop where I bought a bedroom carpet said that when the time came to get the stairs and landing carpet done they would send someone out to measure for me, no problem. Must be much easier for them this way around than having to redo a job later when the measurements weren't right!
Yes - best to draw it out and ask as they can use the carpet in all sorts of ways on stairs. Our last stairs were several sets of shorter bits of carpets as they used offcuts from the other rooms we were having done