Laser Levels In the last few years, laser levels have gotten more compact and less expensive. Ron demonstrates a state-of-the-art version from Ryobi.
Built into the base of this tool is a rubber suction cup complete with a vacuum pump, which enables you to stick the level to almost any flat surface without any pins, nails or clamps.
First, place the laser level on the wall and press a button to turn on the miniature vacuum pump, which continues to run, holding the instrument securely in place. Adjust the turret until the bubble indicates that the laser is level.
The laser line will continue into the corner and onto the adjacent wall. To check for plumb, rotate the head 90 degrees and again, adjust the level. This will provide you with a perfectly vertical line.
Laser levels like this are especially handy if you're working alone. They also keep you from making a lot of unnecessary marks on your walls.