I've tried various methods of finding studs -
1. Look for nail depressions in the drywall. Sometimes works in a shop or garage, hopeless on finished house walls
2. "Woodpecker method" ... drill a series of 1/16" holes about 1/2" apart, marking those that don't go thru to air. Usually not acceptable for house walls. Once you've found one stud, you can hope they built the wall correctly and look 16" away for the next one.
3. Classic "grope and hope" single LED stud finder, swept across the drywall. Sometimes works OK, other times it's nearly worthless
4. Horizontal multiple LED bar sensors.
The first one I bought was from Home Depot:
https://www.homedepot.com/p/RYOBI-Whole-Stud-Detector-ESF5001/302738348
It "kinda" worked, but was a real dog to use. You had to hold down both of the relatively stiff switches to turn it on or keep it on. So whenever you wanted to mark the wall with a pencil and let go of one switch, the thing turned off. And it took about 10 seconds to restart, slowing the process down very frustratingly.
Then I bought "the good one" -
www.precisionstudsensors.com
This is a real gem! Turns on instantly, one button in the center, nice wide LED bar, deep sensitivity, even a place to store the pencil. WELL worth the money!
I don't recall where I bought it. It's availalble on eBay for $66.40
Find many great new & used options and get the best deals for Precision Sensors Professional Stud Finder NEW at the best online prices at eBay! Free shipping for many products!
www.ebay.com
There are similar units (Franklin Sensors ProSensor 710) made by another company. I don't know how handy they are.