Stairs needs to be a good quality otherwise it will wear really quickly. Looks better if you then have the same on the landing. An alternative is striped up the stairs and pick out a colour from that for the landing. I think the best for the stairs is a wool/acrylic mix. And I think should be 80%wool/20% acrylic. And you need a high density (I think this is right term) - ie the number of strands per square inch (or something) so that the corners of the stairs do not look bare.
Bedrooms do not need to be as high quality as they do not take as much wear - you could use a 100% man made - which if DCs rooms maybe an idea as they can be really stain resistant. I personally though do not like the feel or touch to hand of 100% man made carpets personally so I have gone for a 50%/50% mix. This is about the same price as the better man made ones. Because bedrooms get less wear you do not have to have as high a density though - so the bedroom carpets will be less per square metre than the stairs.
You could probably measure up for the bedrooms yourself - but get someone to measure for stairs/landing as they can do magical jigsaws/templates to save you having loads of waste.
I would really advise using an independent carpet shop and not a Carpet-wise place. The cost difference will be negligible. Your will get much better quality and service from the independents. The "sales" prices at Carpet-notwise etc are balls - apparently they have a store under their head office with ridiculously inflated non-sale prices so they say everything in the showrooms is on sale.
See if you can get a local recommendations.
If it helps - my DCs bedroom carpet (being fitted today) was about £16 per m/sq. 50/50 wool/acrylic. 30 density (I think - or could be 40). I needed underlay and gripper rods too - so for the 2 rooms and fitting is £850.
OP - hope you don't mid if I join in with some Qs of my own...
I want to get all of upstairs and the landing/stairs done, but I can't get my head around the logistics of dealing with all the furniture. Is this going to eb a complete headache? Should I do it in stages?
And is it worth trying to repaint all the skirtings while the carpet is out?
We are doing it in stages (we have a spare bedroom so one bedroom at a time can be empty).
Our local, independent carpet store have been FAB. We have put down a deposit for a huge roll of carpet and they are delivering it and fitting it room by room. After each room is done, we pay them for that particular room.
We are having to repaint the rooms in their entirety, but if I were just doing the skirting, I'd just trim 2 inches off the edge of the carpets and do them before the new carpet goes down.