We just moved into a new home with carpeted stairs and previously lived in a one story with all hardwood floors. With two pets and two humans, we're in dire need of a vacuum that can hold its own in terms of power, but is nimble enough for our narrow staircase. Any suggestions?
I have the Shark DuoClean Lift-Away Upright Vacuum and while I don't have stairs, it comes with an attachment that allows you to vacuum on a staircase. I mainly use it to vacuum my couch but the product images show it's for stairs. It's also great for pet hair! I got mine at Costco.
I have never seen anyone so happy to vacuum than my boyfriend after getting our Dyson V8. We have one cat and it works great at getting all that fur! It comes with two different large attachments - one for hardwood and one for carpet, both do their job very well. (Also comes with a bunch of smaller attachments). I definitely recommend! Only worry would be that battery life is ~40 min. My apartment is tiny so not a problem for us.
We are in love with our Dyson Ball Animal 2. We still have the original, builder-grade carpet in our home and it has looked worn for months. Our Dyson is the only vacuum that fluffs up the cheap carpet (until it gets walked on, of course) and its attachments make our stairs almost look new (again, until we step on it - ha). Dysons are known to "never lose suction" -- it's their whole thing. While it is an impressive machine, it took some practice for me to learn the best way to navigate it on our stairs.
We have the Shark Professional and I think it works well for stairs. The canister lifts away from the base, so you aren’t lugging the whole thing up and down the stairs. It also comes with a pet hair attachment and the hose detaches for hard to reach corners.
I love this vacuum cleaner because you don't need bags. The clear plastic canister lifts over the base of the vacuum cleaner. You open the top lid and dump the debris into the trash can. It's that easy.