On a remodel in Minneapolis, Minnesota, the most valuable gadget on site fit in one hand. An infrared thermometer.
Before drywall went up, it was used to scan walls for cold spots and hidden moisture issues. The readings exposed poor insulation and minor leaks that would have turned into major problems later.
Most people focus on tools that help them install things. Pros rely on gadgets that help them detect problems early. Thermal readers, circuit testers, and digital levels prevent mistakes before they become expensive fixes.
In renovation, accuracy beats speed. The right gadget does not make the job faster. It makes it right.