Way way back in the day, I did residential punchout for cookie- cutter tract housing. Every house had at least one covered box, often two or three. Granted, if it is to code, you can get in the general area, but really it can vary, especially with the less-than-good, less-than-legal rough crews we had. So, for awhile I located boxes with the level idea, sometimes that doesn't work because our less-than-good roughers didn't always put the box at the right depth. So, poking around the suspected area with an offset swiveling screwdriver would find the box after awhile.
The sheetrockers got to covering over so many boxes at one point, that my boss lost it. He blew his top. He visited me on a job where I was locating my third box, and talked with me a minute, then started kicking holes in the wall until he found the box:laughing:.
He told me I had an option for locating the boxes in the future: I either could cut a large section of wall out, like 3'x3', or I could use his "size 12" method:thumbup:. After a couple of houses locating boxes with my foot, the sheetrockers got real asstute at cutting the boxes out:laughing: