Also, the construction site can be used to construct things. You can place it, then use F on it to select what to build, then fire construction material (also in throwing) on it to build. Healing tent works, catapult somewhat works and one of the siege towers, i think the large one, also works. But you need teammates to help you, because most things need 25+ construction material to complete. Weapon rack and the other siege tower don't work.