Priced per unit; vendors typically quote against a primary quantity around 1 unit.
No. Commercial-grade hardware is reusable for years. Buy the frame once and reorder only the printed graphic, which is the cheaper part.
Mechanism grade. An economy unit and a commercial one look alike on paper but the cheap one fails sooner. Pin the hardware grade before comparing.
Related variants of this product are tracked as separate benchmark lines. Match the spec before comparing quotes.