Build Walls With Laser Lines
Here's a huge time-saver if you're building walls in an existing space. Normally you would have to snap a chalk line on the floor, then use a plumb bob or a level with a long straightedge to transfer the floor marks to the ceiling. With a laser that projects a vertical beam, you can skip all these steps.
Just line up the laser where you want the wall to be, and you'll see lines on the ceiling and floor. You can leave the laser in place and build to the laser lines, or you can use the lines to make marks for the top and bottom wall plates. Either
way, it's much faster and easier with a laser. A self-leveling cross-line laser works great for this. You can buy one at home centers or online.