I have an Excel file for my inventory. There's a sheet for each period, not all are filled in yet.
the headers are, Unit Name, # of Figures, # of Bases, Type, Army, Manufacturer, Item # , Painted, Unpainted, Cost, Total, Value, Total figures.
Not as detailed as the OPs and a little disjointed but works for what I need. At least if my heirs find it will give them an idea of what's what and how much it's worth.