10ft x 30ft (300 sq ft)
Priced per unit with quantity breaks. Vendors quote steps at 1 / 5 / 10 / 25 / 50 / 100 / 250 / 500 units, and the per-unit rate drops at each break.
Usually a specification or finishing difference, not the core work. Ask both vendors to quote the identical spec and the gap normally narrows.
The same product family is tracked in 20×30, 10×10, 10×20. Quotes are NOT interchangeable across variants, so match the spec before comparing.