When evaluating a walker wheelchair (often referred to as a rollator-transport chair combo), prioritize frame material, typically aircraft-grade aluminum for a balance of lightweight portability and structural strength. Ensure the weight capacity is at least 300 lbs (136 kg) for standard models or 450 lbs+ for bariatric versions. Key components include 8-inch PVC or PU wheels for multi-terrain stability, dual-braking systems (hand brakes and parking brakes), and ergonomic height-adjustable handles to prevent user fatigue.