Identifying a high-quality sofa involves examining its core construction elements, starting with a sturdy frame built from kiln-dried hardwood or marine-grade plywood rather than soft particle board or plastic. Premium upholstery relies on eight-way hand-tied springs or high-resilience foam cushions wrapped in down feathers for lasting support without sagging. Additionally, inspect tailored stitching details, heavy-duty joinery, and manufacturer warranty terms, which typically indicate superior craftsmanship and longevity.