Desk weight capacity matters more than it looks like it should — a laminate or particleboard top rated for 100 to 150 pounds is fine for a laptop and a lamp, but sags over time under dual monitors, a printer and a stack of books. Solid wood or steel-frame desks rated higher (200-plus pounds) hold up better under a fully loaded setup. Height-adjustable (sit-stand) desks should list both a weight capacity and a height range in inches, not just "adjustable" — ask for both numbers.
A task chair worth buying adjusts in at least four ways: seat height, seat depth (or at least backrest angle), lumbar support position, and armrest height. Seat height range should comfortably cover your leg length with feet flat on the floor; if a store can't demo the adjustment range on the floor model, that's worth noting. Mesh-back chairs breathe better for long sitting; foam-and-fabric backs offer more contoured support but run warmer.
Filing storage is rated for its own weight capacity too — a lateral file cabinet loaded with hanging folders can weigh over 100 pounds fully loaded, and cheaper glide mechanisms will stick or bind under that weight within a year. Built-in cable management (grommets, trays or channels) is a small detail that separates a desk designed for actual computer use from one designed to look good in a photo.
Because most home-office pieces ship with some assembly required — desk legs, chair bases and casters especially — ask what a store's assembly and delivery options actually include before buying a large item off a website rather than off the floor.