Take sorting seriously: Individual stacking baskets that nest ($10 each), or a metal frame that holds multiple removable fabric bags ($35).
Like to roll: A wheeled garment rack with bins ($20 to $40).
Navigate stairs: Lightweight, soft-sided vertically shaped bins,
similar to the loop-handled canvas one (shown, about $20 each). Traditional rectangular baskets are unwieldy and lead to scraped knuckles.