When buying formwork plywood, start with the job instead of only asking for the lowest price. Wall formwork, slab work and temporary platforms do not always need the same thickness. A 12 mm sheet may be enough for light work, while 18 mm or 21 mm is often chosen when support spacing is wider.
It is also worth checking the core, film surface and packing details. Good pallet marks, protected edges and clear quantity records save time when the container arrives. These simple things make the buyer's site work less stressful.