When they did the walls in the garage they layed out slats going across the wall so cant find the main studs so easily
This is a very good method and is almost foolproof. For lathe and plaster walls I take it one step further and build a small stack of magnets — maybe and inch or so long — and then holding it like a pen gently between the fingers it’s possible to pick out the pull from the two small lath nails behind the plaster. For really deep penetration (more than 5/8” say), a 3/4” flat rare earth magnet suspended from a fine string like a pendulum works well too. By hanging the magnet from the thread there’s a lot more sensitivity but it can be liable for false triggers though.I use rare earth magnets to find the drywall screws/nails