How To Inventory A Coin Collection

I have made grids like this for certain series of coins. On this example. a black square means that a coin does not exist and a blue square means that I have it. A diagonal red line indicates a coin that was only issued in sets (NIFC). You can use different colors of shading to indicate, for example, if your coin is in poor condition and needs to be upgraded. You can do these very easily on Excel, or the old-fashioned way with graph paper and fibre-tip pens!