Then they can't bring anything up or down the stairs.

Still, I expect it won't matter - by the time we have reasonably priced robots that can reliably do all housework, that's like 90% of jobs eliminated from society and probably society will collapse.

My kitchen, office, living room, gaming computer, entryway, and bedroom are all separated by sets of stairs.

So that's six robots for me?

This is how I used to solve the roomba-can’t-use-stairs problem.

I’ve now moved to a single floor. Problem solved!