I also replaced a screw in the door latch and I didn't know what sized screw bit I needed so John gave me a few in a small plastic box. Unfortunately, the box was open, when I knocked it over and everything spilled. The floor of the coop is slatted, so I didn't know if they stayed in the coop or fell through. I found one bit and a screw fairly easily but was still missing one or two, many minutes later.
I decided to try to find them with John's big magnet using it both in the coop and under it where some of the straw falls through. The chickens like to scratch around under the coop and when I came with the magnet one hen was doing just that. After a considerable time, I was unsuccessful in finding the bit, but the picture above shows all the stuff I did find (mostly bits of old tools and fencing).
At least I am glad I found all this stuff so the animals won't step on it.