In the top-left corner of the map to Broken Hills, four metal chests can be seen, but seemingly cannot be easily accessed. In order to reach them, go near the top-right corner of the map and click on the half-hex right between the fence and the part of the grid which you click to enter the world map, and then click the half-hex right above the fence. Your character will then briefly walk off-screen and appear on the other side of the fence, which will allow you to make your way to the chests. These chests contain the stock of all four shops in Broken Hills, which can be stolen from safely without losing Karma or affecting your Reputation.