Priced per unit; vendors typically quote against a primary quantity around 1 unit.
It should not be. Setup is per design and per print run, not per SKU when pieces share a run. Ask to consolidate.
Gang designs onto one sheet and standardize sizes. Most of the cost in short pieces is setup and material waste, not the printing.
The same product family is tracked in 8×5, 5×5, 10×13. Quotes are NOT interchangeable across variants, so match the spec before comparing.